Safe Harbor
The safe harbor rule provides two paths to avoid underpayment penalties: pay at least 90% of your current year's tax liability, or pay 100% of last year's tax (110% if your AGI exceeded $150,000). Meeting either threshold means no penalty even if you owe a balance at filing. This is especially valuable for self-employed workers with variable income, since predicting exact annual tax is difficult. The 110% threshold for high earners prevents wealthy taxpayers from dramatically under-paying.
Example
Last year you owed $40,000 in total tax and your AGI was $200,000. Your safe harbor is 110% of last year: $44,000. If you pay at least $44,000 in estimated taxes across four quarters ($11,000/quarter), you owe no penalty — even if your actual liability turns out to be $60,000.
Related calculator
Open Estimated Quarterly Tax Calculator →Related Topics
Alabama Estimated Quarterly Tax
Alabama requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Alaska Estimated Quarterly Tax
Alaska does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
Arizona Estimated Quarterly Tax
Arizona requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Arkansas Estimated Quarterly Tax
Arkansas requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
California Estimated Quarterly Tax
California requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Colorado Estimated Quarterly Tax
Colorado requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 70% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Connecticut Estimated Quarterly Tax
Connecticut requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Delaware Estimated Quarterly Tax
Delaware requires estimated quarterly tax payments if you expect to owe more than $800 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Florida Estimated Quarterly Tax
Florida does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
Georgia Estimated Quarterly Tax
Georgia requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 70% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Hawaii Estimated Quarterly Tax
Hawaii requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 60% of your current year tax liability or 100% of your prior year tax. Payments are due on 2026-04-20, 2026-06-20, 2026-09-20, and 2027-01-20.
Idaho Estimated Quarterly Tax
Idaho does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
Illinois Estimated Quarterly Tax
Illinois requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Indiana Estimated Quarterly Tax
Indiana requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Iowa Estimated Quarterly Tax
Iowa requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on 2026-04-30, 2026-06-30, 2026-09-30, and 2027-01-31.
Kansas Estimated Quarterly Tax
Kansas requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Kentucky Estimated Quarterly Tax
Kentucky requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Louisiana Estimated Quarterly Tax
Louisiana requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 70% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Maine Estimated Quarterly Tax
Maine requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Maryland Estimated Quarterly Tax
Maryland requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 110% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Massachusetts Estimated Quarterly Tax
Massachusetts requires estimated quarterly tax payments if you expect to owe more than $400 in state tax. The safe harbor is paying 80% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Michigan Estimated Quarterly Tax
Michigan requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Minnesota Estimated Quarterly Tax
Minnesota requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Mississippi Estimated Quarterly Tax
Mississippi requires estimated quarterly tax payments if you expect to owe more than $200 in state tax. The safe harbor is paying 80% of your current year tax liability. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Missouri Estimated Quarterly Tax
Missouri requires estimated quarterly tax payments if you expect to owe more than $100 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Montana Estimated Quarterly Tax
Montana requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Nebraska Estimated Quarterly Tax
Nebraska requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Nevada Estimated Quarterly Tax
Nevada does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
New Hampshire Estimated Quarterly Tax
New Hampshire does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
New Jersey Estimated Quarterly Tax
New Jersey requires estimated quarterly tax payments if you expect to owe more than $400 in state tax. The safe harbor is paying 80% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
New Mexico Estimated Quarterly Tax
New Mexico requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
New York Estimated Quarterly Tax
New York requires estimated quarterly tax payments if you expect to owe more than $300 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
North Carolina Estimated Quarterly Tax
North Carolina requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
North Dakota Estimated Quarterly Tax
North Dakota requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Ohio Estimated Quarterly Tax
Ohio requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Oklahoma Estimated Quarterly Tax
Oklahoma requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 70% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Oregon Estimated Quarterly Tax
Oregon requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Pennsylvania Estimated Quarterly Tax
Pennsylvania requires estimated quarterly tax payments if you expect to owe more than $14,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Rhode Island Estimated Quarterly Tax
Rhode Island requires estimated quarterly tax payments if you expect to owe more than $250 in state tax. The safe harbor is paying 80% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
South Carolina Estimated Quarterly Tax
South Carolina requires estimated quarterly tax payments if you expect to owe more than $100 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
South Dakota Estimated Quarterly Tax
South Dakota does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
Tennessee Estimated Quarterly Tax
Tennessee does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
Texas Estimated Quarterly Tax
Texas does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
Utah Estimated Quarterly Tax
Utah requires estimated quarterly tax payments if you have any state tax liability not covered by withholding. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Vermont Estimated Quarterly Tax
Vermont requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Virginia Estimated Quarterly Tax
Virginia requires estimated quarterly tax payments if you expect to owe more than $1,000 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on 2026-05-01, 2026-06-15, 2026-09-15, and 2027-01-15.
Washington Estimated Quarterly Tax
Washington does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.
West Virginia Estimated Quarterly Tax
West Virginia requires estimated quarterly tax payments if you expect to owe more than $600 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Wisconsin Estimated Quarterly Tax
Wisconsin requires estimated quarterly tax payments if you expect to owe more than $500 in state tax. The safe harbor is paying 90% of your current year tax liability or 100% of your prior year tax. Payments are due on the same dates as federal (April 15, June 15, September 15, January 15).
Wyoming Estimated Quarterly Tax
Wyoming does not impose a state income tax, so no state estimated quarterly tax payments are required. Self-employed residents still must make federal estimated tax payments if they expect to owe $1,000 or more.