Tax extension.

In plain English

Filing Form 4868 by the April deadline automatically extends your filing deadline to mid-October. The catch hiding in plain sight: it extends the paperwork, not the payment. Tax owed is still due in April, and interest plus a late-payment penalty run on any unpaid balance from that date. The extension's real use is accuracy: missing documents, complicated years, K-1s that arrive late. You estimate and pay what you'll owe in April, then file the precise return later.

01Why it matters

"I filed an extension so I'm covered" is one of the most expensive misunderstandings in tax filing. The failure-to-file penalty is the big one the extension prevents; the failure-to-pay penalty and interest keep running regardless.

02The math, step by step

You owe roughly $3,000 but your brokerage forms are a mess. You file the extension in April and send $3,000 with it. In September you file the real return showing $2,800 owed: the $200 comes back, no penalties. Filing the same extension with $0 paid means interest and late-payment penalties on $2,800 since April.

03What this is NOT

04Receipts

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