If you filed an extension for your 2011 taxes, Monday, October 15th was the deadline to avoid a monthly 5 percent, late-filing penalty and interest on any balance due. For those in the IRS Fresh Start Penalty Relief Initiative, taxes were due to avoid further penalties and interest because the six-month grace period ended.

October 15, 2012 was also the last day to e-file your 2011 tax return. If you missed the deadline, you now have to file a paper return.

If you missed the last call to e-file, you will need to prepare and mail a paper return. Here are a few helpful tips:

1. Double-Check your figures and Social Security numbers.

2. Check the Tax Tables – Double-check that you have used the right figure from the IRS tax table.

3. Sign and Date Your Form – If you are filing a joint return, both spouses must sign even if only one had income. If you paid someone to prepare your return, they must also sign it.

4. Mail Your Return to the Correct Mailing Address – Find the correct mailing address here.

5. Mailing a Payment – Make the check payable to “United States Treasury” and enclose it with, but not attach it to, the tax return or the Form 1040-V, Payment Voucher, if used. The check should include the Social Security number of the person listed first on the return, daytime phone number, the tax year and the type of form filed.

6. Electronic Payments – Electronic payment options are convenient, safe and secure methods for paying taxes. You can authorize an electronic funds withdrawal, or use a credit or a debit card. For more information on electronic payment options, visit the IRS.

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