Idaho Quarterly Estimated Tax Calculator 2026
Idaho has a flat income tax rate of 5.8%, which is included in your quarterly payment calculation. Use this calculator to estimate your quarterly tax payments including self-employment tax and federal income tax plus Idaho state income tax.
Your 2026 Quarterly Payments — Idaho
Total Annual Tax
$0
Per Quarter
$0
Take Home
$0
Effective Rate
0%
Tax Breakdown
Quarterly Estimated Taxes in Idaho
As a self-employed worker in Idaho, your quarterly estimated tax payments need to cover three components: federal self-employment tax (15.3% on 92.35% of net earnings), federal income tax, and Idaho state income tax. Idaho has a flat income tax rate of 5.8%, which is included in your quarterly payment calculation.
State note: Idaho moved to a flat income tax rate.
Does Idaho Require Separate State Quarterly Payments?
Most states with income tax, including Idaho, require their own separate quarterly estimated tax payments if you expect to owe state income tax. Check your state's tax authority website for state-specific forms and due dates, which may differ from federal deadlines.
2026 Federal Quarterly Due Dates
Regardless of which state you're in, the federal quarterly estimated tax due dates for 2026 are: Q1 — April 15, Q2 — June 15, Q3 — September 15, and Q4 — January 15, 2027. Payments are made using Form 1040-ES and can be submitted via IRS Direct Pay, EFTPS, or by mail.
Other States
No Income Tax States
Idaho Tax Quick Facts
- Income Tax
- Yes
- Tax Type
- flat
- Rate
- 5.80%
- SE Tax Rate
- 15.3%
- SS Wage Base
- $176,100