Filing Requirements 13. How are quarterly estimates calculated?
The sum of estimated payments must equal at least 85% of estimated tax liability for the year, and the amount of each estimated payment must reasonably approximate the tax liability for that quarter. For tax year 2013 and after, if prior year's tax under the CIT or MBT election is $20,000 or less, estimated tax may be based on the prior year's amount in four equal payments, the sum of which equals the previous year's tax liability. If the year's tax liability is expected to be $800 or less, quarterly returns are not required.