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A state agency reviewer once walked me through six Schedules A flagged in pre-submission, and none of the errors were exotic. Four carried the wrong date on line 4, using board approval or owner-notice dates instead of the agency official's signature date. One left the line 3b nonprofit set-aside check blank, and one tried to fold a disaster-relief amount into the Form 8610 Part I totals. Each fix took twenty minutes, and the packet still shipped on time only because the cleanup queue had room.
Schedule A is a one-page attachment to Form 8610 that a housing credit agency files to report each carryover allocation, one per project per calendar year, never as a standalone return. The 10 percent basis test drives whether a carryover is reportable: for allocations made before July 1, meet it by year end; for those after June 30, meet it within six months. Use the December 2024 revision and keep the BIN continuous across multi-building projects.
Key Takeaways
- Schedule A, Form 8610 is how a housing credit agency reports each carryover allocation for the calendar year in which the allocation is made. Attach it to that year’s Form 8610.
- The current Schedule A PDF shows Revision December 2024. Use the latest revision, and check the header on the form.
- The 10 percent basis test hinges on allocation date. For allocations made before July 1, meet the test by year end. For allocations made after June 30, meet it within six months, or return the credit to next year’s returned credit component.
- Use the original BIN for the building across later allocations, including rehab treated as a new building, and keep multi‑building projects straight at the building level.
- For the 2025 filing cycle, Form 8610 with attached Schedules A is due February 28, 2026, and mailed to the IRS Service Center in Philadelphia. Use the same pattern and confirm dates for the current year before you file.
What Form 8610 and Schedule A actually do
Form 8610 is the annual report that reconciles your state housing credit ceiling, annual allocations, returned credits, and the count and dollar amounts tied to Forms 8609 and Schedules A. Schedule A is the one‑page attachment for carryover allocations. The IRS describes Form 8610 as the vehicle agencies use to report annual allocations and to transmit Forms 8609 and Schedules A. The Schedule A PDF itself states that agencies use it to report carryover allocations, and it includes general and specific instructions right on the form.
You should think of Schedule A as the evidence sheet for each carryover. It captures the owner, TIN, whether the allocation is building based or project based, the allocation date and amount, and, if a binding agreement applies, the elected applicable percentages. The header on the current Schedule A shows Rev. December 2024, OMB 1545‑0990.
When to file and where it goes
You file one Form 8610 for the calendar year, attach every Schedule A for carryovers you made in that year, and attach any Forms 8609 you issued. For the 2025 cycle, the due date is February 28, 2026, and the mailing address is the IRS Service Center in Philadelphia, PA 19255‑0549. The form’s instructions list the due date and address, so verify the current‑year due date and do not rely on memory.
Simple filing checklist
- Confirm you are using the current Form 8610 and the current Schedule A PDF.
- Assemble Schedules A only for carryovers made in the calendar year you are reporting.
- Reconcile to the state ceiling, including returned credits and any National Pool amounts.
- Attach in the order the Form 8610 instructions specify, then mail to the listed service center by the due date.
Why the 10 percent basis test drives reportability
The carryover allocation is not a free pass. For allocations made before July 1, the taxpayer must have more than 10 percent of reasonably expected project basis by the end of that calendar year. For allocations made after June 30, the taxpayer has six months from the allocation date. If a pre‑July 1 carryover is not timely verified, you treat it as not made and you do not report it on Schedule A. If a post‑June 30 carryover misses the six‑month mark, you must return it, and it goes into next year’s returned credit component. These rules come from Treasury regulations under section 42, not agency folklore.
Timing rules at a glance
| Trigger | Deadline | Reporting impact |
| Carryover made before July 1 | Meet 10 percent by December 31 of that year | If not verified, treat as not made, do not include on Schedule A |
| Carryover made after June 30 | Meet 10 percent within six months of allocation date | If not verified, return the credit, include as returned credit next year |
These mechanics also align with how Form 8610 tallies returned credits in the ceiling reconciliation.
Pro tip, confirm the verification window the day you sign the allocation document. It prevents end‑of‑year scrambles and avoids reporting allocations you later have to unwind.
How to verify the 10 percent test without back‑and‑forth
You need timely, defensible documentation. Regulations allow an agency to require a basis certification by year end for pre‑July 1 allocations, or within a reasonable time after year end, because the agency must accurately complete Form 8610 and Schedule A. If the certification is late or the support does not actually prove basis, do not report the carryover on Schedule A for pre‑July 1 cases. For post‑June 30 cases, if the six‑month window closes without a valid certification and support, return the credit for next year’s ceiling.
What to collect for verification
- Signed owner certification stating more than 10 percent of reasonably expected project basis was paid or incurred by the applicable deadline.
- Evidence of land and depreciable basis, for example invoices, contracts, canceled checks, bank statements, and ledger detail.
- If project‑based under 42(h)(1)(F), support that the 10 percent test is met at the project level, not per building.
- If a binding agreement locks applicable percentages, include that agreement with lines 6a to 6c on Schedule A completed.
Disaster relief, when the clock can move
In major disaster areas, the IRS allows limited relief, including additional time for the 10 percent test and for placed‑in‑service deadlines, when an agency approves relief under Rev. Proc. 2014‑49. If you grant carryover allocation relief, attach marked copies of the impacted Schedules A to Form 8610 as that procedure directs, and exclude those relief amounts from every line of Form 8610 Part I and Part II – they travel as attachments only and never roll into the ceiling totals. The December 2024 Schedule A includes a checkbox for allocation relief under Rev. Proc. 2014‑49 (when you check that relief box, leave the amended carryover allocation box unchecked – the two cannot be checked together on a relief Schedule A).
BIN assignment and multi‑building projects, keep continuity tight
BINs are the backbone of your audit trail. The 8609 instructions state that the BIN first assigned to a building must be used for any allocation of credit to that building going forward. Rehabilitation treated as a new building should not receive a new BIN if the building already has one. For multi‑building projects, you still issue separate Forms 8609 per building and identify the allocation to each building. Consistent BIN usage across Schedule A and 8609 is non‑negotiable.
BIN tips that save review time
- Always tie Schedule A entries to the BIN that reflects the year the building first received an allocation.
- For project‑based carryovers, track the project total, then specify the portion that applies to each building when you later issue Forms 8609.
- Keep a crosswalk that links Schedule A amounts, applicable percentages, and later 8609s by BIN.
Completing Schedule A, line by line highlights
The Schedule A PDF is a fillable, one‑page form. It asks you to indicate building based or project based, enter the allocation date and amount, and, if a binding agreement exists, enter applicable percentages for acquisition, rehab, and new construction. The general and specific instructions sit right on the form, including the pointer to sections 1.42‑6 and 1.42‑8. Check the revision banner, Rev. December 2024 is the current version as of this writing.
- Line 3a, select building based under 42(h)(1)(E) or project based under 42(h)(1)(F).
- Line 4, the allocation date is when your authorized official signs and dates the allocation document (not the project approval date, the owner's notice date, or the placed‑in‑service date), and it should match the Form 8610 year.
- Lines 6a to 6c, complete only if a binding agreement exists and the owner elected to fix the applicable percentage for a month other than the placed‑in‑service month.
Form 8610 reconciliation, ceiling math without surprises
Form 8610 reconciles the state housing credit ceiling and totals your allocations, including the dollar amounts from all Schedules A for that year. For 2025, the instructions specify how to compute the ceiling, how to count returned credits, what to include from the National Pool, and the due date and mailing address. Use the same structure for the current year, but confirm the updated figures and dates before filing.
Attach in the order the IRS lists
The 2025 instructions tell agencies to attach Forms 8609 first, then Schedules A, then any Schedules A that reflect disaster relief approvals under Rev. Proc. 2014‑49. Following the order helps processing and reduces back‑and‑forth.
Clean carryovers are not a paperwork victory, they are a delivery victory. The form reveals how disciplined your internal process is.
Common filing pitfalls and how to avoid them
- Reporting a pre‑July 1 carryover on Schedule A without timely, adequate 10 percent support. For pre‑July 1 allocations that miss the year‑end basis test, treat the allocation as not made and do not include it on Schedule A for that year.
- Forgetting to return a post‑June 30 allocation that failed the six‑month test, then not moving it into next year’s returned credit component.
- Issuing or listing a new BIN for rehab when the building already has one. Use the first BIN assigned to the building.
- Mismatching Schedule A project totals with later Forms 8609 issued per building. Project‑based allocations must flow through to each building’s 8609 with clear amounts.
- Mailing late or to the wrong address, or skipping the attachment order. Follow the due date and the Philadelphia address in the current instructions.
Simple documentation kit for the 10 percent test
- Owner certification that more than 10 percent of reasonably expected basis was paid or incurred by the deadline that applies.
- Support for land and depreciable basis, for example purchase agreements, invoices, canceled checks, wire confirmations, bank statements, and GL detail.
- If applicable, binding agreement that fixes applicable percentages, and the election details that tie to Schedule A lines 6a to 6c.
Where Accountably helps, in one sentence
If you are short on internal capacity to prepare clean, verifiable carryover packages, Accountably supplies structured offshore delivery with SOPs, standardized workpapers, and layered review so your 10 percent tests, BIN continuity, and Schedule A entries are accurate the first time.
Final checklist before you file
- Confirm you are using Form 8610 and Schedule A with the most recent revisions, currently Rev. 12‑2024 for Schedule A.
- For each carryover, confirm the correct timing window and that the 10 percent certification and support match the allocation date.
- Tie every Schedule A to the correct BIN, and preserve continuity with future 8609s.
- Reconcile ceiling math on Form 8610, including returned credits and any National Pool adjustments.
- File by the due date to the listed IRS Service Center address for the current cycle.
Common Mistakes We See Every Season
Six recurring patterns we see on agency Schedules A. Each one is preventable with a documented step in the annual SOP – none require new software.
Reusable Checklists
These checklists are copy-paste ready for your agency SOP and for reviewer templates. Each item is a discrete action a preparer or reviewer can sign off on before the Form 8610 packet ships.
Carryover allocation intake (per project)
- Confirm the agency's authorized official signed the carryover allocation document, and log the signature date for line 4.
- Capture owner name and address for lines 1a and 1b.
- Enter the TIN on line 2 with dashes (XX-XXXXXXX for an EIN or XXX-XX-XXXX for an SSN), never as nine continuous digits.
- Confirm building-based (§42(h)(1)(E)) or project-based (§42(h)(1)(F)) classification on line 3a and record the choice in the workpaper.
- Check Yes or No on line 3b for the §42(h)(5) nonprofit set-aside. Never leave blank.
- Record the allocation amount on line 5: amount allocated to the building if building-based, or aggregate amount across all buildings if project-based.
- Note whether a binding agreement under §1.42-6 and a percentage-month election under §1.42-8 both apply; if both yes, prepare lines 6a, 6b, and 6c.
- Log the original BIN assigned to the building so later Form 8609s and any rehab allocations use the same number.
Schedule A line-by-line review
- Verify the form revision in use is Rev. December 2024 (Cat. No. 30065T, OMB 1545-0990).
- Confirm lines 1a, 1b, and 2 match the owner record in the agency file.
- Confirm line 3a selects exactly one of building-based or project-based.
- Confirm line 3b shows Yes or No, never blank.
- Confirm line 4 shows the agency official's signature date and the year matches the Form 8610 reporting year.
- Confirm line 5 ties to the supporting allocation document and matches the classification on line 3a.
- If lines 6a, 6b, or 6c are populated, confirm both Reg. §1.42-6 (binding agreement) and Reg. §1.42-8 (percentage-month election) supporting documents are in the file.
- Confirm the amended carryover allocation checkbox at the top of the form is set correctly for the filing scenario.
Form 8610 annual packet assembly
- Confirm the current revisions of Form 8610 and Schedule A (Schedule A is Rev. December 2024 as of this writing).
- Pull every Schedule A for carryovers made during the calendar year being reported.
- Reconcile state housing credit ceiling, returned credits, and National Pool amounts on Form 8610 Parts I and II.
- Attach Forms 8609 first, then Schedules A, then any Rev. Proc. 2014-49 disaster-relief Schedules A as separate attachments.
- Exclude amounts from disaster-relief Schedules A from every line in Form 8610 Part I and Part II.
- Verify the amended carryover allocation box is unchecked on every disaster-relief copy and the Rev. Proc. 2014-49 relief box is checked.
- Confirm the current cycle's due date and the IRS Service Center mailing address from the Form 8610 instructions before mailing.
Keep 8610 Schedule A Season From Stalling
Schedule A season for housing credit agencies is one of the more compressed annual cycles in tax administration. Carryover allocations get signed across the calendar year, but the verification, BIN tracking, and Schedule A assembly all converge on a single Form 8610 due date in the following year. Per the Schedule A instructions (Rev. December 2024), one Schedule A is filed per project per calendar year, and Rev. Proc. 2014-49 disaster-relief copies travel as attachments excluded from Form 8610 Part I and Part II totals. Missing either rule turns the packet into a manual rework job.
The fix is not heroics in February. It is a workflow that captures the right data at the moment each allocation is signed, then standardizes how reviewers walk through line items, BIN continuity, and ceiling reconciliation.
- Capture line 4 signature dates and line 5 amounts at the allocation event, not from board minutes or owner correspondence three months later.
- Maintain a BIN ledger per project that survives staff turnover. The first BIN assigned to a building must follow it through every later allocation and any rehabilitation treated as a new building.
- Use a two-trigger gate for lines 6a, 6b, and 6c so they stay blank unless both a binding agreement under Reg. §1.42-6 and an applicable-percentage election under Reg. §1.42-8 are documented.
- Segregate Rev. Proc. 2014-49 disaster-relief Schedules A from the working file used for Form 8610 totals so the amounts cannot accidentally roll into Parts I and II.
- Run a one-Schedule-A-per-project check at packet assembly so multi-building projects do not slip in duplicate Schedules A within the same calendar year.
Accountably runs the production layer behind clean Schedule A and Form 8610 packets through structured workpapers, two-layer review, and SOPs aligned with IRC §42 and the Schedule A instructions. See our taxation services for how that delivery layer plugs into the agency workflow.
FAQs
What is Form 8586, and how does it relate to Form 8610?
Form 8586 is how owners claim the Low‑Income Housing Credit as part of the general business credit. Agencies do not file Form 8586, but your Form 8610 and Schedule A data ultimately support what owners claim, through the Forms 8609 you issue.
Is there an “8610‑2” form?
No. Agencies file Form 8610, attach Schedules A for carryovers, and issue Forms 8609. If you heard “8610‑2,” the speaker probably meant Schedule A or Form 8609. You can find the current Form 8610 and Schedule A on the IRS site pages for those forms.
How do I handle a project split across multiple buildings on Schedule A?
If the carryover is project based under 42(h)(1)(F), list it on a single Schedule A for the project in the allocation year with the Line 5 amount reflecting the credit allocated to all the buildings in the project (not one building's share), keep the original BINs per building consistent, and when buildings place in service, issue Forms 8609 that show the portion of the project allocation applied to each building.
Where do I find the current due date and mailing address for Form 8610?
The due date and the IRS Service Center mailing address appear in the Form 8610 instructions. For the 2025 cycle, the filing deadline is February 28, 2026, and the address is Philadelphia, PA 19255‑0549. Confirm the current year before you file.
Do rehab allocations get a new BIN?
No. The 8609 instructions say that rehabilitation expenditures treated as a separate new building should not receive a new BIN if the building already has one. Use the number first assigned to the building.