In this guide
Owners follow the split in who should own TIN compliance: AP for onboarding, tax for notices and filing, one shared record. Ticks are saved in this browser only; a printed copy has empty boxes.
The year at a glance
The compliance year at a glance
Feb. 1, 2027NEC, W-2, 9451099-NEC and W-2 to recipients and the IRS; Form 945. January 31 is a Sunday. No automatic extension.
Mar. 1 / Mar. 31Other 1099sPaper by March 1 (fewer than 10 returns in total only); e-file by March 31. 1042-S March 15.
AprilSpring CP2100 runB-Notices out within 15 business days; withholding by business day 30.
July or OctoberNotice 972CGProposed penalty for the returns filed the year before; 45 days to respond.
August 1Correction tier closesCorrections after this date are penalized at the top rate.
Sept. to Oct.Fall CP2100 runThe first run for the returns filed that spring. Same clock.
DecemberW-9 sweep, W-8 expiryAnnual solicitations by the 31st; re-solicit expiring W-8s; reconcile withholding for the 945.
Dates for tax year 2026 returns filed in 2027. The interactive compliance calendar has every date for 2026 and 2027.
At vendor onboarding, before the first payment
Owner AP
- Collect a signed Form W-9 (U.S. payees) or the correct Form W-8 (foreign payees). Log the request date and the receipt date. Solicitation rules
- Check the TIN format before submitting it anywhere. Format checker
- Run the name/TIN pair through IRS TIN matching. Record the result code and the date. Interactive matching takes 25 pairs per request and 999 pairs in total in 24 hours; for a whole vendor file, use a bulk file (up to 100,000 pairs, results within 24 hours). How matching works
- If the result is 2 or 3, go back to the vendor with a specific question (personal name vs. business name; legal name vs. DBA) and get a corrected W-9 before the first payment. The result codes
- Screen the legal name, DBA and signatory against OFAC SDN and Consolidated lists, plus SAM and LEIE if you're federally funded or in healthcare. Log the list date and result. Sanctions screening
- If no TIN was furnished and you're paying anyway, set the vendor to backup withholding at 24% from the first payment. Backup withholding
Monthly
Owner AP, with tax for withholding
- Re-screen the active vendor master when OFAC updates its lists. OFAC sets no fixed frequency and leaves it to your own policies and procedures (OFAC FAQ 28), so write the frequency into your policy. Sanctions screening
- Review the backup-withholding vendors: confirm withholding is actually being applied on payments, and deposits are on schedule. Deposits and Form 945
- Follow up on outstanding W-9 requests older than 30 days.
When a CP2100 or CP2100A arrives (spring and fall)
Owner Tax
- Day 0: log the notice date and the date received. Run the deadline calculator.
- Compare every listed account to your current records. Do not send a B-Notice for accounts already corrected, or where the error was yours. CP2100 guide
- Determine first vs. second notice for each account (same account listed within the previous three calendar years?).
- By business day 15: mail First B-Notices with a W-9, or Second B-Notices with agency-validation instructions and no W-9. Envelope marked "Important Tax Information Enclosed." Templates
- By business day 30: begin 24% backup withholding on any listed payee who hasn't responded.
- As responses arrive: verify the new pair and update the record. First notice: stop withholding within 30 calendar days after the payee gives you a W-9 certifying a correct TIN. Second notice: a new W-9 is not enough; stop only once the payee gives you the SSA or IRS validation. CP2100 guide
- File the notice, the mailing list, the mailing date and the responses; retain three years.
December
Owner AP for the sweep, tax for the reconciliation
- Sweep every active vendor with no TIN on file and send the first-annual (or second-annual) solicitation by December 31. Log it. This is the step that preserves the penalty waiver. Why
- Re-run TIN matching on every vendor paid a reportable amount this year whose pair hasn't been verified, or whose W-9 changed. Bulk matching
- Re-solicit expiring W-8s. A W-8BEN or W-8BEN-E generally expires on the last day of the third calendar year after it was signed (forms signed in 2023 expire December 31, 2026), sooner if a change in circumstances makes it incorrect. Get the new form before the first payment of the new year. W-8 validity calculator
- Reconcile backup withholding withheld vs. deposited in preparation for Form 945. Deposits and Form 945
January through March: the filing deadlines
Owner Tax
Three different clocks run in the first quarter: statements to payees, returns to the IRS, and the withholding return. The 1099-NEC and W-2 are the odd ones out: due to the IRS on the same day as the recipient copy, with no automatic extension. A due date on a weekend or holiday moves to the next business day; the dates below are for tax year 2026 returns filed in 2027.
| What | Due | Notes |
|---|---|---|
| Recipient copies: 1099-NEC, 1099-MISC, 1099-INT, 1099-DIV, 1099-K, W-2, W-2G | Feb. 1, 2027 | January 31 is a Sunday. |
| 1099-NEC and W-2 to the IRS and SSA | Feb. 1, 2027 | Paper or electronic, same date. Form 8809 is granted only for hardship and must be filed by the due date. |
| Form 945 for 2026 backup withholding | Feb. 1, 2027 | Feb. 10 if every deposit was made on time and in full. |
| Recipient copies: 1099-B, 1099-S, 1099-DA, 1099-MISC with box 8 or box 10 | Feb. 16, 2027 | February 15 is Presidents' Day. |
| Paper filing to the IRS: 1099-MISC, INT, DIV, K, W-2G, 1098 series | March 1, 2027 | Paper is allowed only if you file fewer than 10 information returns in total; otherwise e-file is mandatory. |
| Forms 1042 and 1042-S | March 15, 2027 | Recipient copies of the 1042-S are due the same day. |
| E-file to the IRS: 1099-MISC, INT, DIV, K, B, S, DA, W-2G, 1098 series | March 31, 2027 | Form 8809 filed by this date gives an automatic 30-day extension (not for NEC or W-2). |
Source: 2026 General Instructions for Certain Information Returns (IRS Publication 1099), "When To File," "Statements to Recipients" and "Extension of Time To File"; Form 1042-S instructions for the March 15 date. The compliance calendar has every date for 2026 and 2027 with the weekend and holiday shifts applied, and exports to your calendar. The figures page has the thresholds behind each form.
- Apply the threshold for the year the payments were made: for payments made in 2026, the 1099-NEC and 1099-MISC threshold that was $600 is $2,000, and for payments made in 2027 it is $2,100 (Rev. Proc. 2026-35). 2026 figures
- File 1099s with the corrected TINs; show backup withholding in box 4. Where a pair is still known-bad, file anyway (a late return is penalized on top of an incorrect one) and note it for the expected CP2100.
- File on time even if some records are wrong, then correct. A return filed by the due date and corrected within 30 days is penalized at the lowest tier; a return held back to fix it is penalized as late. How to correct
- Count your returns before January: 10 or more of any kind combined means every one must be e-filed. Paper filers over the limit are penalized as if they had not filed. The waiver, as the IRS decides it
- Reconcile Form 945 line 2 to total backup withholding in box 4 across the 1099s before filing either. Checker
When a Notice 972CG arrives (12 to 18 months after filing)
Owner Tax
- Log the notice date; the response is due in 45 days (60 if outside the U.S.).
- Check the count and tiers against your corrected-return dates. Penalty estimator
- Pull the solicitation log and B-Notice records for every listed payee. What counts as a solicitation
- Write the reasonable-cause statement, attach the exhibits, sign under penalties of perjury, and send before the deadline. 972CG guide · Template
- Agree and pay the items you can't defend, and fix the onboarding gap that caused them.
Records to keep, and for how long
Owner AP and tax, in one shared record
- W-9s and W-8s: while the vendor is active plus four years.
- Solicitation log (date, method, response): four years after the related return's due date.
- TIN match results and sanctions screening results with dates: four years.
- CP2100 notices, B-Notices sent, withholding start/stop dates: at least three years after the first notice, to apply the second-notice rule.
- Forms 945 and deposit records: four years.