HMRC videos on understanding your tax code
Source: gov.uk (2025-01-16)

Learn more about how tax codes work and reporting a change of circumstances.

Tax code letters and numbers

Watch a video about what your tax code is and how it is used by your employer or pension provider.

What is a tax code? (https://www.youtube.com/watch?v=0f0wu1UsWQw)

You will learn about:
- what the numbers in your tax code mean
- your tax-free amount for the year
- why there are letters in tax codes
How tax codes work

Watch a video about how your tax code helps you pay the right amount of tax.

How does a tax code work? (https://www.youtube.com/watch?v=SYOKyw9g0Tw&t=37s)

You will learn about:
- your tax code and tax-free amount
- how your tax-free amount is used if you are paid weekly or monthly
- different rates of tax and tax rate bands
- how to estimate your income tax for the year
Emergency tax codes

Watch a video about emergency tax codes, also known as temporary tax codes.

What is an emergency tax code? (https://www.youtube.com/watch?v=KOSEBEmvyKw&list=PL8EcnheDt1zj_OmyzLDsh5SmBFrz-avu7&index=3)

You will learn about:
- W1, M1 and X tax codes
- how emergency tax codes work
- why you might have an emergency tax code
- how long you will have an emergency tax code
Changes that can affect your tax code

Watch a video about why your tax code might change.

What changes can affect my tax code? (https://www.youtube.com/watch?v=XGOupHs4TNY&list=PL8EcnheDt1zj_OmyzLDsh5SmBFrz-avu7&index=4)

You will learn about:
- what changes can affect your tax code
- income changes and your tax code
- how your tax code helps you pay the right amount of tax
- tax codes and additional sources of income
- tax codes and company benefits
Tax code changes and your pay

Watch a video to find out how tax code changes affect your pay.

How do changes to my tax code affect my pay? (https://www.youtube.com/watch?v=WVJpaPhKGew&list=PL8EcnheDt1zj_OmyzLDsh5SmBFrz-avu7&index=5)

You will learn about:
- tax code changes when your tax-free amount increases
- tax code changes when your tax-free amount reduces
- tax code changes when you get a taxable company benefit
- in-year adjustments to collect tax underpayments
Updating your details if your tax code is wrong

Watch a video about what you can do if your details are not up to date.

How can I update my details online if my tax code is wrong? (https://www.youtube.com/watch?v=dfMH6Q1xsVA)

You will learn about:
- your personal tax account
- automatic tax code changes
- when you can update your details
- updating your employment or pension details
- updating your existing income
- adding a missing company benefit
- what happens when you update your details
Starting a new job without a P45

Watch a video about what information to give your employer if you do not have a P45.

Starting a new job without a P45 (https://www.youtube.com/watch?v=GrfDskRvdwc)

You will learn about:
- finding your National Insurance number
- completing and previewing the starter checklist
- sending the starter checklist to your employer
Give us feedback

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