<PAGE>

                                    FORM 10-Q


                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


    [ X ]         QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                              THE SECURITIES EXCHANGE ACT OF 1934

                For the quarterly period ended September 30, 1997

                                       OR

    [   ]         TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                              THE SECURITIES EXCHANGE ACT OF 1934

   For the transition period from ____________________ to ___________________

                       Commission File number 33-11773-01


                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
             (Exact name of registrant as specified in its charter)

<TABLE>
<S>                                           <C>
                  Texas                                   76-0226425
(State or other jurisdiction of organization) (I.R.S. Employer Identification No.)
</TABLE>


                        16825 Northchase Drive, Suite 400
                              Houston, Texas 77060
                    (Address of principal executive offices)
                                   (Zip Code)

                                  (281)874-2700
              (Registrant's telephone number, including area code)

                                      None
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  Registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements for the past 90 days.

Yes  X      No
   ----       ----



<PAGE>


                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.

                                      INDEX




<TABLE>
<CAPTION>
PART I.    FINANCIAL INFORMATION                                                      PAGE
 <S>                                                                                  <C>
 ITEM 1.    Financial Statements

  Balance Sheets

      - September 30, 1997 and December 31, 1996                                       3

  Statements of Operations

      - Three month  and nine month periods ended September 30, 1997 and 1996          4

  Statements of Cash Flows

      - Nine month periods ended September 30, 1997 and 1996                           5

  Notes to Financial Statements                                                        6

 ITEM 2.    Management's Discussion and Analysis of Financial
                Condition and Results of Operations                                    7

PART II.    OTHER INFORMATION                                                          9


SIGNATURES                                                                            10
</TABLE>

<PAGE>

                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                                 BALANCE SHEETS



<TABLE>
<CAPTION>
                                                                                        September 30,        December 31,
                                                                                            1997                 1996
                                                                                       ---------------      ---------------
                                                                                         (Unaudited)
         <S>                                                                           <C>                  <C>           
         ASSETS:

         Current Assets:
              Cash and cash equivalents                                                $        1,723       $      107,525
              Oil and gas sales receivable                                                    277,621              442,490
              Receivable due to property disposition                                               --              108,997
              Other                                                                            10,016                   --
                                                                                       ---------------      ---------------
                   Total Current Assets                                                       289,360              659,012
                                                                                       ---------------      ---------------

         Oil and Gas Properties, using full cost
              accounting                                                                   24,834,756           24,669,072
         Less-Accumulated depreciation, depletion
              and amortization                                                            (20,824,715)         (20,363,813)
                                                                                       ---------------      ---------------
                                                                                            4,010,041            4,305,259
                                                                                       ---------------      ---------------
                                                                                       $    4,299,401       $    4,964,271
                                                                                       ===============      ===============

         LIABILITIES AND PARTNERS' CAPITAL:

         Current Liabilities:
              Accounts payable and accrued liabilities                                 $      218,713       $      200,096
                                                                                       ---------------      ---------------

         Deferred Revenues                                                                    216,052              220,394

         Partners' Capital                                                                  3,864,636            4,543,781
                                                                                       ---------------      ---------------
                                                                                       $    4,299,401       $    4,964,271
                                                                                       ===============      ===============
</TABLE>



                 See accompanying notes to financial statements.

                                        3


<PAGE>

                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




<TABLE>
<CAPTION>
                                                    Three Months Ended                  Nine Months Ended
                                                       September 30,                       September 30,
                                              ---------------------------------  ---------------------------------
                                                    1997             1996             1997             1996
                                              ---------------   ---------------  ---------------   ---------------
<S>                                           <C>               <C>              <C>               <C>            
REVENUES:
   Oil and gas sales                          $       294,699   $       383,621  $       888,971   $     1,396,958
   Interest income                                      1,142               954            3,740             2,712
   Other                                                2,040             6,509            7,953            23,712
                                              ---------------   ---------------  ---------------   ---------------
                                                      297,881           391,084          900,664         1,423,382
                                              ---------------   ---------------  ---------------   ---------------

COSTS AND EXPENSES:
   Lease operating                                    123,008           129,998          395,123           384,657
   Production taxes                                    17,078            17,629           44,390            62,305
   Depreciation, depletion
     and amortization -
       Normal provision                               105,696           113,890          304,805           425,664
       Additional provision                                --             4,650          156,097             4,650
   General and administrative                          25,644            58,216          147,831           189,923
   Interest expense                                       229                --              229             9,566
                                              ---------------   ---------------  ---------------   ---------------
                                                      271,655           324,383        1,048,475         1,076,765
                                              ---------------   ---------------  ---------------   ---------------
NET INCOME (LOSS)                             $        26,226   $        66,701  $      (147,811)  $       346,617
                                              ===============   ===============  ===============   ===============



Limited Partners' net income (loss)
   per unit                                   $           .10   $           .26  $          (.57)  $          1.33
                                              ===============   ===============  ===============   ===============
</TABLE>



                 See accompanying notes to financial statements.

                                        4


<PAGE>
                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)

<TABLE>
<CAPTION>
                                                                                           Nine Months Ended
                                                                                             September 30,
                                                                               ----------------------------------------
                                                                                    1997                      1996
                                                                               ---------------         ----------------
<S>                                                                             <C>                     <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
    Income (Loss)                                                               $     (147,811)         $       346,617
    Adjustments to reconcile income (loss) to
      net cash provided by operations:
      Depreciation, depletion and amortization                                         460,902                  430,314
      Change in gas imbalance receivable
          and deferred revenues                                                         (4,342)                 (24,065)
      Change in assets and liabilities:
        (Increase) decrease in oil and gas sales receivable                            164,869                   94,314
        (Increase) decrease in receivable due to property disposition                  108,997                       --
        (Increase) decrease in other current assets                                    (10,016)                  (7,886)
        Increase (decrease) in accounts payable
          and accrued liabilities                                                       18,617                 (786,109)
                                                                               ---------------          ---------------
               Net cash provided by (used in) operating activities                     591,216                   53,185
                                                                               ---------------          ---------------
CASH FLOWS FROM INVESTING ACTIVITIES:
    Additions to oil and gas properties                                               (165,684)                 (55,839)
    Proceeds from sales of oil and gas properties                                           --                  397,324
                                                                               ---------------          ---------------
               Net cash provided by (used in) investing activities                    (165,684)                 341,485
                                                                               ---------------          ---------------
CASH FLOWS FROM FINANCING ACTIVITIES:
    Cash distributions to partners                                                    (531,334)                (349,818)
    Payments on note payable                                                                --                  (42,669)
                                                                               ---------------          ---------------
               Net cash provided by (used in) financing activities                    (531,334)                (392,487)
                                                                               ---------------          ---------------
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS                                  (105,802)                   2,183
                                                                               ---------------          ---------------
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD                                       107,525                    1,039
                                                                               ---------------          ---------------
CASH AND CASH EQUIVALENTS AT END OF PERIOD                                      $        1,723          $         3,222
                                                                               ===============          ===============
Supplemental disclosure of cash flow information:
    Cash paid during the period for interest                                    $          229          $        10,637
                                                                               ===============          ===============
</TABLE>



                 See accompanying notes to financial statements.

                                        5


<PAGE>


                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                          NOTES TO FINANCIAL STATEMENTS
                                   (UNAUDITED)


(1)  General Information -

                  The financial statements included herein have been prepared by
        the  Partnership  and are  unaudited  except  for the  balance  sheet at
        December  31,  1996  which has been  taken  from the  audited  financial
        statements at that date. The financial  statements reflect  adjustments,
        all of which  were of a  normal  recurring  nature,  which  are,  in the
        opinion  of  the  managing   general   partner   necessary  for  a  fair
        presentation.  Certain  information  and footnote  disclosures  normally
        included in financial  statements  prepared in accordance with generally
        accepted  accounting  principles have been omitted pursuant to the rules
        and regulations of the Securities and Exchange Commission  ("SEC").  The
        Partnership  believes adequate disclosure is provided by the information
        presented.  The financial  statements should be read in conjunction with
        the audited  financial  statements  and the notes included in the latest
        Form 10-K.

(2)  Gas Imbalances -

                  The  gas  imbalance   receivable  and  deferred  revenues  are
        accounted  for on  the  entitlements  method,  whereby  the  Partnership
        records its share of revenue,  based on its entitled amount. Any amounts
        over or under  the  entitled  amount  are  recorded  as an  increase  or
        decrease  to the  gas  imbalance  receivable  or  deferred  revenues  as
        applicable.

(3)  Vulnerability Due to Certain Concentrations -

                  The  Company's  revenues are  primarily the result of sales of
         its oil and natural gas  production.  Market  prices of oil and natural
         gas may fluctuate and adversely affect operating results.

                  The Partnership extends credit to various companies in the oil
         and gas industry which results in a concentration  of credit risk. This
         concentration  of credit risk may be affected by changes in economic or
         other conditions and may accordingly  impact the Partnership's  overall
         credit risk.  However,  the Managing  General Partner believes that the
         risk is mitigated by the size, reputation,  and nature of the companies
         to which the Partnership  extends credit. In addition,  the Partnership
         generally  does not  require  collateral  or other  security to support
         customer receivables.

(4)  Fair Value of Financial Instruments -

                  The Partnership's  financial  instruments  consist of cash and
         cash equivalents and short-term  receivables and payables. The carrying
         amounts  approximate  fair value due to the highly liquid nature of the
         short-term instruments.


                                       6


<PAGE>

                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                       CONDITION AND RESULTS OF OPERATIONS

GENERAL

      The  Partnership  was formed for the purpose of investing in producing oil
and gas properties  located within the  continental  United States.  In order to
accomplish  this,  the  Partnership  goes through two  distinct yet  overlapping
phases  with  respect  to its  liquidity  and  result  of  operations.  When the
Partnership  is formed,  it commences its  "acquisition"  phase,  with all funds
placed in short-term  investments until required for such property acquisitions.
The interest  earned on these  pre-acquisition  investments  becomes the primary
cash flow source for initial partner distributions.  As the Partnership acquires
producing   properties,   net  cash  from  operations   becomes   available  for
distribution,  along with the investment  income.  After  partnership funds have
been expended on producing oil and gas properties,  the  Partnership  enters its
"operations" phase. During this phase, oil and gas sales generate  substantially
all revenues,  and  distributions  to partners  reflect those  revenues less all
associated  partnership expenses.  The Partnership may also derive proceeds from
the sale of acquired oil and gas properties, when the sale of such properties is
economically appropriate or preferable to continued operation.

LIQUIDITY AND CAPITAL RESOURCES

      The  Partnership  has  completed  acquisition  of  producing  oil  and gas
properties,  expending all of the limited  partners'  commitments  available for
property acquisitions.

      The  Partnership  does  not  allow  for  additional  assessments  from the
partners  to fund  capital  requirements.  However,  funds  in  addition  to the
remaining  unexpended net capital commitments of the partners are available from
partnership  revenues,  borrowings  or  proceeds  from the  sale of  partnership
property.  The  Managing  General  Partner  believes  that the  funds  currently
available to the Partnership  will be adequate to meet any  anticipated  capital
requirements.

RESULTS OF OPERATIONS

      The  following  analysis  explains  changes  in the  revenue  and  expense
categories  for the quarter  ended  September  30, 1997  (current  quarter) when
compared to the quarter ended September 30, 1996  (corresponding  quarter),  and
for the nine months ended September 30, 1997 (current period),  when compared to
the nine months ended September 30, 1996 (corresponding period).

Three Months Ended September 30, 1997 and 1996

     Oil and gas sales  declined  $88,922 or 23 percent in the third  quarter of
1997 when  compared  to the  corresponding  quarter  in 1996,  primarily  due to
decreased oil and gas production.  A decline of 36 percent in oil production and
4 percent in gas production had a significant impact on partnership performance.
Also,  current quarter oil prices declined 21 percent or $4.21/BBL when compared
to third quarter 1996 oil prices, further contributing to decreased revenues.

      Associated depreciation expense decreased 7 percent or $8,194.

     The Partnership recorded an additional provision in depreciation, depletion
and amortization in the third quarter of 1996 for $4,650 when the present value,
discounted  at ten percent,  of estimated  future net revenues  from oil and gas
properties,  using the guidelines of the Securities and Exchange Commission, was
below the fair market  value  originally  paid for oil and gas  properties.  The
additional  provision results from the Managing General Partner's  determination
that the fair market  value paid for  properties  may or may not  coincide  with
reserve  valuations  determined  according to guidelines of the  Securities  and
Exchange Commission.


                                       7


<PAGE>

                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
                 CONDITION AND RESULTS OF OPERATIONS (CONTINUED)


Nine Months Ended September 30, 1997 and 1996

     Oil and gas sales decreased $507,987 or 36 percent in the first nine months
of 1997 over the  corresponding  period in 1996.  A decline of 25 percent in gas
production and 49 percent in oil production were major  contributing  factors to
the  decreased  revenues  for the period.  Increased  gas prices of 9 percent or
$.19/MCF partially offset the production declines.

      Associated depreciation expense declined 28 percent or $120,859.

     The Partnership recorded an additional provision in depreciation, depletion
and  amortization  in the first nine  months of 1997 and 1996 for  $156,097  and
$4,650,  respectively,  when the present  value,  discounted at ten percent,  of
estimated future net revenues from oil and gas properties,  using the guidelines
of the  Securities  and  Exchange  Commission,  was below the fair market  value
originally paid for oil and gas  properties.  The additional  provision  results
from the Managing  General  Partner's  determination  that the fair market value
paid for properties may or may not coincide with reserve  valuations  determined
according to guidelines of the Securities and Exchange Commission.

      During 1997,  partnership  revenues  and costs will be shared  between the
limited partners and general partners in a 90:10 ratio.


                                       8


<PAGE>


                    SWIFT ENERGY INCOME PARTNERS 1987-B, LTD.
                           PART II - OTHER INFORMATION



ITEM 5.    OTHER INFORMATION


                                     -NONE-




                                       9


<PAGE>


                                   SIGNATURES



Pursuant to the  requirements of Section 13 or 15(d) of the Securities  Exchange
Act of 1934,  the  Registrant  has duly  caused  this report to be signed on its
behalf by the undersigned thereunto duly authorized.


                                        SWIFT ENERGY INCOME
                                        PARTNERS 1987-B, LTD.
                                        (Registrant)

                             By:        SWIFT ENERGY COMPANY
                                        Managing General Partner


Date:  November 4, 1997      By:        /s/ John R. Alden
       ----------------                 ---------------------------------------
                                        John R. Alden
                                        Senior Vice President, Secretary
                                        and Principal Financial Officer

Date:  November 4, 1997      By:        /s/ Alton D. Heckaman, Jr.
       ----------------                 ---------------------------------------
                                        Alton D. Heckaman, Jr.
                                        Vice President, Controller
                                        and Principal Accounting Officer


                                       10