Guide  ·  Form 1040

Schedule 3, line 6a.

An individual claims the federal R&D tax credit (Section 41) on Schedule 3 (Form 1040), line 6a, whether it was computed on their own Form 6765 or arrived on a Schedule K-1. Form 3800 sits between. This guide covers only what is specific to Form 1040.

Schedule 3, line 6aGeneral business credit, with Form 3800 attached. Line 8 carries to Form 1040, line 20. Checked against the 2025 form.
Line 4iof Form 3800 is where a sole proprietor reports it, as an eligible small business.
Column (c)of Form 3800 holds the entity EIN when the credit came on a K-1.

The route

Form 1040 (2025)
StepForm and lineRevision checked
Compute the creditForm 6765, line 30 (sole proprietor), or the K-1 amount (owner of a pass-through)Form 6765 (Rev. December 2024)
Apply the limitationForm 3800, Part III, line 1c, or line 4i for an eligible small business, then Part II, line 38Form 3800 (2025)
Claim on the returnSchedule 3 (Form 1040), line 6a, General business credit, attach Form 3800; line 8 carries to Form 1040, line 20Schedule 3 (Form 1040) 2025
Deduct the research costSection 174A deduction on Schedule C, Part V, line 27a; amortized amounts on Form 4562, Part VIInstructions for Form 4562 (2025)
Amend a prior yearForm 1040-XIRS amended-return FAQ

Steps for the preparer

  1. A sole proprietor attaches Form 6765 completed through line 30. A sole proprietorship is an eligible small business when average annual gross receipts for the three prior years are $50 million or less, so line 30 goes to Form 3800, Part III, line 4i. The Form 6765 guide covers each section.
  2. An owner of a partnership or S corporation takes the amount from Schedule K-1 (Form 1065), box 15, code M, or Schedule K-1 (Form 1120-S), box 13, code M, and enters it on Form 3800, Part III, line 1c, with the entity EIN in column (c). No Form 6765 is needed unless the individual also has research of their own.
  3. Passive or not. A credit from an activity the taxpayer does not materially participate in goes through Form 8582-CR first and lands in column (d). Otherwise use column (e). The Form 3800 guide covers the rest of the limitation.
  4. Enter Form 3800, line 38 on Schedule 3, line 6a. Line 8 of Schedule 3 carries to Form 1040, line 20.
  5. Report the expense. For tax years beginning after December 31, 2024, domestic research or experimental expenditures are deducted in the year paid or incurred under Section 174A, or capitalized and amortized over not less than 60 months by election. Foreign research stays under Section 174 and is amortized over 15 years. Amortized amounts are reported on Form 4562, Part VI, with 174A in column (d). Revenue Procedure 2025-28 sets out the transition choices for costs capitalized in 2022 through 2024. For a Schedule C business the current deduction is an other expense in Part V, line 27a.

Amended returns

Form 1040-X

Common questions

Can a sole proprietor make the payroll tax election?

No. The election is limited to corporations, S corporations, and partnerships. A sole proprietor claims the credit against income tax through Form 3800.

Does the credit offset self-employment tax?

No. The general business credit reduces the income tax on Form 1040, line 18. Self-employment tax on Schedule 2 is not reduced.

What if the individual has no income tax this year?

The unused credit carries back one year and forward twenty. Form 3800 tracks it.

Sources

Related guides

  • Form 6765Completing Form 6765, the credit form itself.
  • Form 3800Where the research credit goes on Form 3800 and how it reaches the return.
  • Form 1120C corporations: Schedule J, Section 174A, and Form 1120-X.
  • Form 1120-SS corporations: Schedule K line 13g, K-1 box 13 code M, and the shareholder.
  • Form 1065Partnerships: Schedule K line 15f, K-1 box 15 code M, and the partner.
  • Form 1041Estates and trusts: Schedule G line 2b and K-1 box 13 code I.

The study arrives with Form 6765 complete.

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