#tax-deadlines
Important tax filing deadlines and compliance dates to remember
A January 1 payroll cutover is the cleanest one because a single provider owns all four Forms 941, the Form 940, and every W-2 — but it takes roughly twelve weeks of prep. This checklist covers the October-to-January timeline, the year-to-date and fringe-benefit data that must migrate, Form 8655 authorization and revocation, and the five handoff mistakes that generate IRS notices.
For 2026 the section 402(g) elective deferral limit is $24,500 per person ($32,500 with the age-50 catch-up, $35,750 at ages 60 to 63), aggregated across every 401(k), 403(b), SIMPLE IRA and SARSEP you contribute to in the year. An excess not refunded with earnings by April 15 is taxed twice, once as wages in the contribution year and again on distribution. Steps include totaling W-2 Box 12 deferrals, notifying the plan in writing, reading 1099-R codes P and 8, and capping payroll after a mid-year job change.
Under Section 7502 a return mailed on or before its due date is deemed filed on the postmark date — but only if it actually arrives, and a postage-meter date never counts. Since December 24, 2025, USPS postmarks reflect regional processing rather than deposit, so certified mail or a free manual postmark is the proof that holds.
Since January 2025, Swiss businesses with taxable turnover up to CHF 5,005,000 and three clean filing periods can elect one annual VAT return through the SFTA ePortal instead of quarterly returns, but still pay advance installments on May 30, August 30 and November 30. Here is who qualifies, why the end-of-February election deadline matters, when quarterly filing is the better cash-flow choice, and the monthly bookkeeping habits that make annual filing safe.
How small growers keep books that answer "which crop made money?" — Schedule F expense categories, why cash accounting fits a market garden, the March 1 / January 15 farmer estimated-tax rule, the farm optional method for Social Security credits, and per-enterprise cost allocation by bed-feet and labor hours.
A superseding return is a complete second return filed before the deadline (including extensions) that legally replaces your original, unlike a Form 1040-X amendment filed after it. It preserves elections reserved for original returns and can stop interest and penalties — but when filed during an extension period it does not reset the three-year assessment or refund clocks, which run from the first valid return.
Indiana's Tax Amnesty 2026 runs July 15 through September 9, 2026 and waives all penalties, interest, and collection fees on DOR-administered taxes for periods ending before January 1, 2024, provided you pay in full or open a payment plan that is paid off by June 7, 2027. This guide covers the eligibility checklist (including the 2005/2015 prior-participant bar), the four-step INTIME process, five mistakes that void the waiver, and how to record the forgiven amounts in your books.
SECURE 2.0 Section 120 lets a departing employee's $1,000–$7,000 401(k) balance follow them into their next employer's plan through the Portability Services Network, and IRS Notice 2024-2 requires most calendar-year plans to adopt a consolidated SECURE 2.0 amendment by December 31, 2026. This guide covers how auto-portability interacts with force-out rules, what the amendment must memorialize, whether small employers should opt in, and the payroll, census and expense records to reconcile before year-end.
Form 4868 gives a sole proprietor an automatic six-month extension to file Form 1040 and Schedule C — moving the 2025 return deadline from April 15 to October 15, 2026 — but the tax itself was still due in April. How to estimate total liability including self-employment tax, request the extension electronically or through a designated payment, and limit the 5%-per-month failure-to-file penalty.
Hit one estimated-tax safe harbor and the IRS underpayment penalty disappears — pay 90% of this year's tax or 100% of last year's (110% if prior-year AGI topped $150,000) through timely quarterly payments. Covers the 2026 penalty rate (7% Q1/Q3, 6% Q2, compounded daily), the four due dates, and a bookkeeping system that keeps you penalty-free.
South African freelancers pay provisional tax in two IRP6 installments — 31 August and 28/29 February — by estimating full-year taxable income themselves; missing a deadline or estimating below 90% of actual income triggers a 10% late-payment penalty, a 20% underestimation penalty, and interest from the effective date.
The IRS requires S-corp and C-corp Designated Officials to revalidate Business Tax Account access every June 15 through July 29 or lose online access to payments, transcripts, and notices until they reapply from scratch.
