TIN Compliance Calendar 2026–2027: Every 1099, 945 and W-9 Date

TIN compliance calendar: every date for 2026 and 2027

Filing and statement due dates, Form 945, the solicitation deadlines, the CP2100 and 972CG seasons, penalty tiers and W-8 expiry, on one calendar. Filter by category, add your own CP2100 or account-opening dates and get the computed deadlines placed on the same grid, then download it or subscribe.

Covers 2026 and 2027Updated September 22, 2026Sources General Instructions for Certain Information Returns; Pub 1281; Reg. 301.6724-1; Form 945 instructionsPrivacy your own dates stay in this browser

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Add your own dates

Computed with the same business-day rules as the calculators (weekends and federal holidays skipped). Saved in this browser only; nothing is sent anywhere.

Date on a CP2100 or CP2100A notice

Date an account was opened without a TIN

Date on a Notice 972CG

I backup withhold: show monthly Form 945 deposit dates (15th, monthly depositor)

How the dates were set

Due dates that fall on a Saturday, Sunday or legal holiday move to the next business day (IRC 7503); the moved date is the one shown. Penalty tiers use the amounts for returns due in 2026 (Rev. Proc. 2024-40). The CP2100 and 972CG entries mark the seasons in which the IRS usually mails those notices, not fixed dates; your own notice date sets your deadlines, which is what the “Add your own dates” panel is for. Form 945 deposit dates assume a monthly depositor; semiweekly depositors follow the Wednesday/Friday schedule in the Form 945 guide. Every figure and date is sourced on the figures page.