If I owe 25,000 in taxes and I file a year late what would the penalty be

If you owe money, you would be a lot better off if you filed and set up an installment agreement to pay the IRS.

A failure to file penalty is charged on returns filed after the due date or extended due date, absent a reasonable cause for filing late. The combined penalty is 5% (4.5% late filing and 0.5% late payment) for each month or part of a month that your return was late, up to 25%.

The failure to pay penalty is one-half of one percent for each month, or part of a month, up to a maximum of 25% of the amount of tax that remains unpaid from the due date of the return until the tax is paid in full.

For more information see the IRS website: Eight Facts on Late Filing and Late Payment Penalties