Tax Day has come and gone, and we hope you filed your tax return, or at least requested an extension.

If you didn't get around to filing, the federal government is not going to haul you away in chains.

However, the Internal Revenue Service would still like to see your return, and the sooner the better. There is a penalty for failing to file a return, but the closer you are to the deadline, the smaller that penalty will be.

If you're due a refund, there is no penalty for filing late, but if you don't file within three years, you lose your refund.

If you had a good reason for failing to file on time (perhaps you were receiving a heart transplant), the IRS may consider reducing the penalties, though the agency is not allowed to reduce the interest charges. Even people who have died are required to file a tax return, and their survivors could end up paying penalties if they file late. (Post continues below video.)

Here is some additional advice from the IRS for taxpayers who didn't file their returns on time:

• Electronic filing is your best option, and you can do that through Oct. 15, the due date for taxpayers who asked for extensions to file.
• You can still file for free, using Free File.
• If you can't pay everything you owe, pay as much as you can. Then ask for an installment plan for the rest of your obligation.

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• 'Disaster' looms for 2013 tax season
• Some taxpayers get 6 extra months to pay