New federal tax credits were authorized in the Patient Protection and Affordable Care Act (ACA; P.L. 111-148 , as amended), to help certain individuals pay for health insurance coverage, beginning in 2014. The tax credits apply toward premiums for private health plans offered through exchanges (also referred to as health insurance marketplaces ). The ACA also authorized subsidies to reduce cost-sharing expenses. This report describes the eligibility criteria applicable to the premium tax credits and cost-sharing subsidies, and the calculation method for the credit and subsidy amounts. It also highlights selected issues addressed in the final regulation and guidance on premium credits and indicates the status of implementation, where relevant data is available. Health insurance exchanges operate in every state and the District of Columbia (DC), per the ACA statute. Exchanges may be established and administered by states, the federal government (administered through the Department of Health and Human Services [HHS]), or a combination of both. Exchanges are not insurance companies; rather, they are marketplaces that offer private health plans to qualified individuals and small businesses. Generally, exchange plans provide a comprehensive set of health services and meet all of the ACA's insurance market reforms, as applicable. In addition, most exchange plans comply with a requirement that measures how much a given plan will pay for a group of individuals (who vary in terms of medical use and expenses); that measure is referred to as actuarial value (AV). Most exchange plans meet a specific AV, with each AV designated by a precious metal: bronze (actuarial value of 60%), silver (70%), gold (80%), and platinum (90%). For AVs, the higher the percentage, the lower the cost sharing, on average . Given that the ACA specifically requires exchanges to offer insurance options to individuals and small businesses, the ACA requires exchanges to be structured to assist these two different types of "customers." Consequently, there is an exchange to serve individuals and families, and another to serve small businesses (SHOP exchanges ) within each state. However, the ACA gives states the option to provide one exchange to serve both individuals and small businesses. Certain enrollees in the individual exchanges are eligible for premium assistance in the form of federal tax credits. Such credits are not provided through the SHOP exchanges. The premium credit is an advanceable, refundable tax credit, meaning tax filers need not wait until the end of the tax year to benefit from the credit and may claim the full credit amount even if they have little or no federal income tax liability. Receiving the credits as advanced payments means that monthly insurance premiums will be automatically reduced by the credit amount. Therefore, the direct cost of insurance to an individual/family generally will be lower than the "advertised" cost for a given exchange plan. The Treasury Department (Treasury) promulgated final regulation on the premium credits on May 23, 2012. The final regulation confirmed certain eligibility and other requirements, as specified in statute; such requirements are discussed in applicable sections of this report. In addition, the Internal Revenue Service (IRS) has issued guidance and other documentation (such as Q&As) relevant to premium credits. The ACA specifies that premium credits will be available to "applicable taxpayers" in a "coverage month." An applicable taxpayer is an individual who is part of a tax-filing unit; is enrolled in a plan through an individual exchange; and has household income at or above 100% of the federal poverty level (FPL), but not more than 400% FPL. A coverage month refers to a month in which the applicable taxpayer paid for coverage offered through an exchange, not including any month in which the taxpayer was eligible for "minimum essential coverage" with exceptions. These eligibility criteria are discussed in greater detail below. Premium assistance is provided in the form of tax credits, which are administered through the tax system (although advance payments go directly to insurers). The premium credit process requires qualifying individuals to file federal tax returns, even if their incomes are at levels that normally do not necessitate the filing of tax returns. Married couples are required to file joint tax returns to claim the credit. The final regulation includes special rules relating to the calculation and allocation of credit amounts due to changes in filing status during a given tax year (e.g., taxpayers who marry or divorce). The final regulation acknowledges that certain circumstances may make filing jointly a challenge (e.g., domestic abuse, abandonment, etc.); it states that the IRS will propose additional rules to address these kinds of circumstances. Premium credits are available only to individuals and families enrolled in a plan offered through an individual exchange; premium credits are not available through the small business (SHOP) exchanges. Individuals may enroll in a plan through their state's exchange if they are (1) residing in a state in which an exchange was established; (2) not incarcerated, except individuals in custody pending the disposition of charges; and (3) "lawfully present" residents. Only lawful residents are allowed to obtain exchange coverage. Undocumented individuals are prohibited from purchasing coverage through an exchange, even if they could pay the entire premium without a subsidy. Because the ACA prohibits undocumented individuals from obtaining exchange coverage, they are not eligible for premium credits. The final regulation clarifies the potential credit eligibility for family members of individuals who themselves are not eligible to enroll in an exchange due to incarceration or legal status. For example, while the final regulation restates the ACA's prohibition on incarcerated individuals enrolling in exchange plans, the rule confirms that family members (of incarcerated individuals) who enroll in exchange plans may receive premium credits, as long as the family members meet all eligibility criteria. Individuals generally must have household income within statutorily defined guidelines (based on the federal poverty level [FPL] ) to be eligible for premium credits, with some exceptions. For purposes of premium credit eligibility, household income is measured according to the definition for modified adjusted gross income (MAGI). An individual whose MAGI is at or above 100% FPL up to and including 400% FPL may be eligible to receive premium credits. Table 1 displays the income levels at 400% FPL, the amount beyond which individuals and families would not be eligible for premium credits in 2015 (using 2014 HHS poverty guidelines). To receive a premium credit, an individual may not be eligible for "minimum essential coverage," with exceptions (described below). The ACA broadly defines minimum essential coverage to include Medicare Part A; Medicare Advantage; Medicaid (with exceptions); the State Children's Health Insurance Program (CHIP); Tricare; Tricare for Life, a health care program administered by the Department of Veterans Affairs (VA); the Peace Corps program; any government plan (local, state, federal) including the Federal Employees Health Benefits Program (FEHBP); any plan offered in the individual health insurance market; any employer-sponsored plan (including group plans regulated by a foreign government); any grandfathered health plan; any qualified health plan offered inside or outside of exchanges; and any other coverage (such as a state high risk pool) recognized by the HHS Secretary. The ACA provides certain exceptions regarding eligibility for minimum essential coverage and receipt of premium credits: An individual who is only eligible to obtain coverage through the individual (nongroup) health insurance market may be eligible to receive a premium credit. An individual eligible for an employer-sponsored plan may still be eligible for premium credits if the employer's coverage is either (1) not affordable; that is, the employee's premium contribution toward the employer's self-only plan exceeds 9.56% of household income; or (2) does not provide minimum value; that is, the plan's payments cover less than 60% of total allowed costs on average. An individual who is eligible for limited benefits under Medicaid may still be eligible for premium credits (see " Medicaid " section below for additional information). Certain small employers (and in later years, large employers at state option) may offer and contribute toward coverage through SHOP exchanges. If an individual is enrolled in an exchange through an employer who contributed toward that coverage, the individual will not be eligible for premium credits. The ACA's Medicaid expansion provisions have the potential for affecting eligibility for premium credits if certain low to middle income individuals and families seek health insurance through the exchanges. Under the ACA, states have the option to expand Medicaid eligibility to include all non-elderly, non-pregnant individuals (i.e., childless adults and certain parents, except for those ineligible based on certain non-citizenship status) with income up to 138% FPL. (The ACA does not change noncitizens' eligibility for Medicaid. ) States that have chosen to implement the ACA Medicaid expansion have received substantial federal subsidies. If a person who applied for premium credits in an exchange is determined to be eligible for Medicaid, the exchange must have them enrolled in Medicaid. Therefore, in states that have expanded Medicaid eligibility to include persons with incomes at or above 100% FPL (or any state that currently includes such individuals), premium credit eligibility begins at the income level where Medicaid eligibility ends. In general, a person may be eligible for only one subsidized health coverage program at a time. However, exceptions are made for individuals who are eligible only for limited benefits under Medicaid; limited benefits include the pregnancy-related benefits package, treatment of emergency medical conditions only, and other limited benefits. Individuals who have access to specified limited benefits under Medicaid may qualify for premium credits if such individuals enroll in exchanges. The amount of the premium tax credit varies from person to person; the credit is based on the household income of the tax filer (and dependents), the premium for the exchange plan in which the tax filer (and dependents) is (are) enrolled, and other factors. In certain instances, the credit amount may cover the entire premium and the tax filer pays nothing toward the premium. In other instances, the tax filer may pay part (or all) of the premium. The credit amount is based on a comparison of two amounts that result from two different scenarios. The first scenario (and amount) is straightforward: the premium for the exchange plan in which the person/family enrolls. The second scenario is more complicated, involving a formula that considers the premium for a reference plan in the local area in which the person/family resides, and an amount that the person/family may be required to contribute toward the premium. Based on a comparison of the amounts resulting from each scenario, the premium credit will be the lesser amount. The following text box, "Calculation of the Premium Credit Amount," discusses these two scenarios in more detail. Under Scenario B, the amount that a tax filer who receives a premium credit is required to contribute toward the premium (for the reference plan) is capped as a percentage of household income; that is, the maximum premium contribution is the product of the tax filer's household income and the "applicable percentage," as specified in the ACA. In general, the applicable percentage is less for those with lower incomes compared with those with higher incomes; where income is measured relative to the federal poverty level. Under Scenario B, the amount that tax filers with income between 100% FPL and 133% FPL may be required to contribute toward the reference plan's premium is capped at 2.01% of household income for 2015. For tax filers with income 300%-400% FPL, their premium contribution is capped at 9.56% of income. The IRS further specifies the applicable percentages, for tax filers whose incomes are between those two income bands (see Figure 1 ). The line graph shows the "applicable percentage" used to calculate the tax filer's required premium contribution at each income level, as measured relative to the federal poverty level. The ACA statute specifies the applicable percentage at certain incomes (income at 100% FPL, 133% FPL, 150% FPL, etc.) beginning in 2014 and indexed in later years. At each of those incomes, the line changes slope. Specifically, at and above 133% FPL up to 300% FPL, the applicable percentage increases incrementally as income increases. For example, a person with income at 150% FPL may be required to pay a maximum of 4.02% of household income toward exchange coverage in the reference plan. A 1% increase in income (i.e., person has income at 151% FPL) results in a maximum premium contribution equal to 4.07% of income. In contrast to this gradual change in the maximum premium contribution for incomes between 133% and 300% FPL, there is a "cliff" for a person/family with income below 133% FPL. Instead of the incremental change discussed above, the contribution amount jumps when you compare income just below 133% FPL with income at 133% FPL. This cliff reflects statutory requirements. Given that calculation of the premium credit amount (under Scenario B) is the arithmetic difference after subtracting the tax filer's required premium contribution from the premium for the second-lowest-cost silver plan ( reference plan ), it is theoretically possible that a person's required premium contribution could be equal to or exceed the reference plan's premium. Such a scenario would leave that tax filer with a premium credit of zero. Moreover, while the credit amount under this scenario is based on the reference plan, the individual/family may enroll in any metal-tier plan and still be eligible for credits. However, when a premium credit recipient enrolls in a plan that is more expensive than the reference plan, that person must pay the additional premium amount. For 2015, Table 2 displays selected annual income levels used in the calculation of premium credit amounts and required premium contributions, as discussed above. Table 3 displays the maximum monthly premium contributions for individuals and families who receive premium tax credits, provided that they enroll in the applicable reference plan. Both Figure 1 and Table 3 illustrate the cliff effect that occurs at 133% FPL. For individuals with income below 133% FPL, the credit formula ensures that such individuals pay no more than 2.01% of their income for the second-lowest-cost silver plan. For incomes at 133% FPL, individuals and families may pay 3.02% of their income toward premiums for the reference plan. For example, an individual with income at 132.99% FPL (annual income of $15,520) may be required to pay $26 in monthly premiums for the second-lowest-cost plan in 2015 (see Table 3 ). With one additional dollar of income (annual income of $15,521, equivalent to 133% FPL), this person may be required to pay $39 in monthly premiums. Therefore, the additional $1 in annual income may lead to an additional $156 in premium contributions for this hypothetical person in 2015. Nevertheless, some might observe that prior to implementation of the ACA premium credits in 2014, there were no federal subsidies for health coverage for individuals with income at this level and above, except for some narrowly defined groups. Thus, more individuals overall may be eligible for subsidized private coverage under the ACA, than before enactment of the law. The following hypothetical examples use actual exchange information about premiums, enrollee contributions, and estimated premium credit amounts; the information was compiled using the plan finder tool at healthcare.gov. To facilitate comparisons across hypothetical individuals and families, the premium and estimated tax credit amounts apply to the same zip code: 60647 (the same zip code used as an example in the plan finder tool at https://www.healthcare.gov/see-plans/ ). The examples in Table 4 assume that the hypothetical individual (or family) is enrolled in the reference plan (second-lowest-cost silver plan). As the 2015 premium data indicate, individuals at the same income level will face different (pre-credit) premiums based on age. This reflects the limited age rating allowed for health insurance policies, including those offered in the individual exchanges. The practical effect of the ACA's age rating requirements means that, for any given metal-tier plan in a specific geographic area, premiums vary for adults between 21 and 64+ years of age by a 3:1 ratio. (For examples that illustrate the 3:1 ratio for adults, see hypothetical persons A, B, C, and D in Table 4 and the following analysis included under " Discussion of Self-Only Coverage Examples .") Moreover, the premium credit amounts are greater for those with lower incomes, compared with higher-income individuals of the same age, reflecting the income-based structure of the premium credits. As indicated Table 4 the monthly (pre-credit) premiums for self-only coverage in the second-lowest-cost silver plan in zip code: 60647, are $168 for a 21-year-old individual and $506 for a 64-year-old individual. Given the 3:1 age-rating among adults between 21 and 64+ years of age, it follows that the premium for the same plan in the same county is approximately three times greater for the older adults (hypothetical persons B and D), than it is for the younger adults (hypothetical persons A and C). That is, hypothetical persons A and C (both of whom are 21 years of age) have a pre-credit premium of $168, compared to hypothetical persons B and D (both of whom are 64 years of age) who have a pre-credit premium of $506. However, for premium credit recipients, age does not determine the amount that a given person contributes toward the premium. The formula for calculating premium contributions from enrollees is based on income (see Table 3 ), and such contributions are calculated prior to determining the credit amount. Therefore, the actual amount that tax credit recipients will pay toward exchange premiums may be the same for individuals with the same income levels, regardless of age. For example, persons A and B are very different in age but have the same income level; therefore, their required monthly contributions toward premiums are the same amount ($59). Person C is an example of the exception to this general rule. Persons C and D have the same income level, so you would expect their premium contributions to be the same amount ($325, see Table 3 ). However, person C's pre-credit premium ($168) is lower than the maximum premium contribution allowed for an enrollee at that income level ($325). Therefore, person C pays the entire premium amount for the second-lowest-cost silver plan available in that zip code. The rules applicable to self-only coverage regarding age-rating for adults and calculation of enrollee premium contributions based on income likewise apply to family coverage. Table 4 includes 2015 examples for hypothetical families comprised of two adults of the same age and one child who is age 19. Similar to the self-only coverage examples, the families with the older adults (families F and H) face a larger pre-credit premium than the families with the younger adults (families E and G). However, the families with the same income pay the same amount toward premiums (see families E and F), unless the maximum premium contribution exceeds the pre-credit premium (see family G). Under the ACA, the amount received in premium credits is based on the prior year's income tax returns. These amounts are reconciled when individuals file tax returns for the actual year in which they receive premium credits. If a tax filing unit's income decreases during the tax year, and the filer should have received a larger tax credit, this additional credit amount will be included in the tax refund for the year. On the other hand, any excess amount that was overpaid in premium credits will have to be repaid to the federal government as a tax payment. However, the ACA imposes limits on the excess amounts to be repaid under certain conditions. For households with incomes below 400% FPL, the law includes specific limits that apply to single and joint filers separately—limits that will be indexed by inflation in future years. Since the enactment of the ACA, these limits have been legislatively amended twice: first under the Medicare and Medicaid Extenders Act of 2010 ( P.L. 111-309 ), and then under the Comprehensive 1099 Taxpayer Protection and Repayment of Exchange Subsidy Overpayment Act of 2011 ( P.L. 112-9 ). The current repayment limits vary by income band (see Table 5 ). For example, say a family received overpayments for the tax credits they should have received in a given tax year. They will have to repay the excess when they file federal income taxes for that year. However, if such a family has income below 200% FPL, the IRS may only require them to repay up to $600 (for tax credit overpayments during that tax year). In other words, while such a family may technically owe a larger amount, repayment is limited to a maximum of $600 for a family with income below 200% FPL. On January 26, 2015, the IRS announced that premium credit recipients who owe a payment on their 2014 tax return, as a result of the tax credit reconciliation process, may receive limited tax relief. For the 2014 tax year only, taxpayers who meet specified eligibility criteria will be given relief from penalties related to the following scenarios: (1) late payment of taxes owed and (2) underpayment of taxes owed. In other words, this relief for 2014 only applies to penalties related to late payment or underpayment of taxes; the relief does not negate the taxpayer's obligation to pay back excess premium credit amounts calculated under the reconciliation process. Moreover, this limited relief does not provide taxpayers with an extension to file their return, nor does it provide relief from any underpayment related to the penalty for not complying with the ACA's individual mandate. To qualify for penalty relief under the first scenario, taxpayers must otherwise be in compliance with other tax filing and payment requirements; owe a tax payment as a result of premium credit overpayments that were advanced during the 2014 tax year; and report the excess amount of advanced credit payments on their timely filed 2014 tax return. To qualify for penalty relief under the second scenario, taxpayers must otherwise be in compliance with other tax filing and payment requirements and report the excess amount of advanced credit payments on their timely filed 2014 tax return. On March 10, 2015, HHS announced that nearly 11.7 million persons selected a metal plan through the individual exchanges, with 86% determined to be eligible for premium tax credits. These data reflect exchange plan selections through the standard open enrollment period as well as the special enrollment period (SEP) that ended on February 22, 2015. For 2015 exchange enrollment, HHS is providing another special enrollment period. This SEP is for individuals residing in states in which the federal government administers the exchanges who were uninsured in 2014 and are subject to the penalty for noncompliance with the individual mandate. Individuals who meet the requirements specified in the SEP announcement will be allowed to enroll in an exchange plan during the SEP (March 15, 2015, through April 30, 2015). In its past and current estimates of the ACA's health coverage provisions, the Congressional Budget Office (CBO) projects exchange enrollment to be modest in the first few years, then increase significantly afterwards. Likewise, the estimates of federal outlays for premium credits are relatively moderate initially, but increase rapidly after the first few years. According to its latest estimates, CBO projects exchange enrollment in 2015 to total 12 million persons: 11 million and 1 million persons enrolled in the individual and SHOP exchanges, respectively. By 2025, CBO estimates that 25 million individuals will be enrolled in exchange coverage. Of those exchange enrollees who are enrolled in the individual exchanges (22 million), 16 million are projected to receive premium credits (see Figure 2 ). CBO estimates that federal outlays for premium credits will total $599 billion from FY2016 through FY2025. In addition to the premium credits, the ACA established subsidies that are applicable to cost-sharing expenses. An individual who qualifies for the premium credit and is enrolled in a silver plan (actuarial value of 70%) through an exchange is also eligible for cost-sharing assistance. The assistance is provided in two forms, and both forms are based on income (see descriptions below). Individuals who receive cost-sharing subsidies may receive both types, as long as they meet the applicable eligibility requirements. The ACA requires each metal tier plan to limit the total amount an enrollee will be required to pay out of pocket for use of covered services in a year (referred to as an annual cost-sharing limit in this report), and establishes separate limits for self-only coverage and family coverage. For 2015, the annual cost-sharing limit for self-only coverage is $6,450; the corresponding limit for family coverage is $12,900. Given that tiered plans will already be required to comply with those annual cost-sharing limits, one form of cost-sharing assistance reduces such limits (see Table 6 ). The cost-sharing assistance reduces the annual limit faced by eligible individuals with income between 100% and 250% FPL; greater reductions are provided to those with lower incomes. In general, this cost-sharing assistance targets individuals and families who use a great deal of health care in a year and, therefore, have high cost-sharing expenses. Enrollees who use very little health care do not generate enough cost-sharing expenses to reach the annual limit. The second form of cost-sharing assistance also applies to individuals with income between 100% and 250% FPL. For eligible individuals, the cost-sharing requirements (in the plans they have enrolled) have been reduced to ensure that the plan covers a certain percentage of allowed health care expenses, on average. The practical effect of this cost-sharing assistance is to increase the actuarial value (AV) of the exchange plan in which the person is enrolled ( Table 7 ), so enrollees face lower cost-sharing requirements than they would have without this assistance. Given that this form of cost-sharing assistance directly affects cost-sharing requirements (e.g., lower deductible), both enrollees who use minimal health care and those who use a great deal of services may potentially benefit from this assistance. To be eligible for cost-sharing subsidies, an individual must be enrolled in a silver plan, so that coverage already has an AV of 70%. For an individual who receives the subsidy referred to in Table 7 , the health plan imposes a set of different cost-sharing requirements, so the "silver" plan will meet the new applicable AV. The ACA statute does not specify how a plan reduces cost-sharing requirements to increase the AV from 70% to one of the higher AVs. Through regulations, HHS requires each insurance company that offers a plan that is subject to these cost-sharing reductions to develop variations of its silver plan; these silver plan variations must comply with the higher levels of actuarial value (73%, 87%, and 94%). When an individual is determined by an exchange to be eligible for a cost-sharing subsidy, the person is enrolled in the plan variation that corresponds with that person's income (as indicated in Table 7 ). This approach allows an individual to benefit automatically from this type of assistance, as soon as he or she uses health care that is covered under the exchange plan. The HHS Secretary will provide full reimbursements to exchange plans that provide cost-sharing subsidies. A given health plan is required to submit to HHS estimates of the amount of cost-sharing assistance it will provide in a year. Such estimates must be submitted prior to that year to receive advance payments for the estimated amount of cost-sharing assistance. A plan also must submit to HHS actual amounts of cost-sharing assistance provided. The actual amounts will be periodically reconciled with the amounts received by the plan in advance payments. CBO estimates that federal outlays for the cost-sharing subsidies will total $136 billion from FY2016 through FY2025. 

Summary: New federal tax credits, authorized under the Patient Protection and Affordable Care Act (ACA; P.L. 111-148, as amended), first became available in 2014 to help certain individuals pay for health insurance. The tax credits apply toward premiums for private health plans offered through exchanges (also referred to as health insurance marketplaces). The ACA also established subsidies to reduce cost-sharing expenses. Health insurance exchanges operate in every state and the District of Columbia (DC), per the ACA statute. Exchanges may be established and administered by states, the federal government, or a combination of both. Exchanges are not insurers, but they provide eligible individuals and small businesses with access to private health insurance plans. Generally, plans offered through the exchanges provide a comprehensive set of health services and meet all of the ACA's insurance market reforms, as applicable. The new premium credits established under the ACA are advanceable and refundable, meaning tax filers need not wait until the end of the tax year to benefit from the credit and may claim the full credit amount even if they have little or no federal income tax liability. Premium tax credits generally are available to individuals who enroll in an exchange plan; are part of a tax-filing unit; have household income between specified amounts; are not eligible for other forms of comprehensive health coverage; and are U.S. citizens or lawfully present residents. This report provides examples of hypothetical individuals and families that qualify for the premium credits. The examples use actual 2015 exchange premiums. The amounts received in premium credits are based on federal income tax returns. These amounts are reconciled after individuals file their returns and can result in overpayment of premium credits if income increases, which must be repaid to the federal government. The ACA limits the amount of required repayments for lower-income enrollees. In addition to premium credits, the ACA authorized new cost-sharing subsidies. Certain premium credit recipients also are eligible for reductions in their annual cost-sharing limits. Moreover, certain low-income individuals receive additional subsidies in the form of reduced cost-sharing requirements (e.g., lower deductibles).