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Home > Guides > Mailing a State Tax Return
There is no single address: each state's revenue department publishes different mailing addresses depending on your return type and whether you enclose a payment. Check your state revenue department's mailing-addresses page or the instruction booklet for your specific form before mailing.
| What you're sending | Which address to use |
|---|---|
| Individual return, no payment (refund or zero balance) | The "without payment" address for your form type |
| Individual return with a check enclosed | A different "with payment" address, which routes to the payment processing unit |
| Amended return | Usually a separate address from the original return |
| Extension or estimated-tax voucher alone | Its own address, often with a different zip-plus-four suffix |
| Business return (corporate, partnership, LLC) | Separate addresses from individual returns |
State revenue departments run mailrooms like sorting machines. Returns with checks go to payment-processing units where the payment and return stay attached; returns without payments go to scanning units that feed directly into processing. Even a single digit in a zip-plus-four code can route your envelope to a different processing unit inside the same agency, so "close enough" is not good enough. California's Franchise Tax Board, for example, publishes distinct Sacramento PO boxes for returns with and without payments, and the addresses differ again for business returns. This pattern holds in most states.
The instruction booklet that comes with your return form lists the mailing address, and most state revenue departments keep a dedicated mailing-addresses page online. Use the booklet for the current tax year, not last year's, because PO boxes and routing suffixes change. If you moved during the year or are filing a part-year return, confirm you're using the resident-return address for the state where you're filing, since some states split resident, nonresident, and part-year returns across addresses.
Yes. The IRS and state agencies both treat the postmark as the filing date, and certified mail gives you a mailing receipt plus proof the agency received it. Keep the certified mail receipt stapled to your copy of the return. An unsigned return is considered invalid, so sign it (both spouses, if joint) before it goes in the envelope. Keep copies of everything: the return, every schedule and form, W-2s, and the payment voucher. If the return is ever questioned, your copy plus the certified mail receipt is your entire defense.
Make the check payable exactly as the instructions say, usually the revenue department's full name, and write your Social Security number and the tax year on the memo line so the payment credits the right account. Never mail cash. If you e-filed and are mailing only a payment voucher, use the payment-voucher address from the voucher's instructions, not the return address. Mailing a payment to the wrong unit can delay processing by weeks even if the check itself is correct.
Most states now offer free or low-cost e-filing, and it usually processes faster with an instant confirmation. Mailing makes sense when you have an unusual situation: a return the e-file system won't accept, paper-only forms, or a preference for a paper trail you fully control. If you do mail, time it so the envelope arrives before the filing deadline, and remember that the postmark, not the arrival date, is what counts.
This is general information, not tax advice.
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