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WMT

Base Period Calculator — Which Quarters Count

Pick the month you file and see exactly which calendar quarters count toward your estimate: the standard base period of the first four of the last five completed quarters, the lag quarter many states add in an alternate base period, and which weeks sit right on the boundary of both windows.

Works offline — your inputs never leave this device. How that works

Q1 2025
Jan–Mar 2025
Q2 2025
Apr–Jun 2025
Standard base period
Q3 2025
Jul–Sep 2025
Standard base period
Q4 2025
Oct–Dec 2025
Standard base period
Q1 2026
Jan–Mar 2026
Standard base period
Q2 2026
Apr–Jun 2026
Lag quarter (alternate only)
Q3 2026
Jul–Sep 2026
You file here

Standard base period — the four highlighted quarters: the first four of the last five completed calendar quarters before the week you file. The most recent completed quarter (the "lag quarter") is skipped because employers have not yet reported those wages.

Alternate base period — many states check the last four completed quarters (including the amber lag quarter) if you do not qualify with the standard window. Each state page on this site says whether its agency offers one, with the agency's own wording.

Timing tip in fact form: filing a few weeks earlier or later can move an entire quarter of wages into or out of your base period — the diagram shows exactly which weeks sit on the boundary. Your state agency makes the official determination from reported wages.

🎓 Understand this tool

What it is

A diagram of which calendar quarters a state counts when it computes a claim, based on the month you file — including the lag quarter that the standard window leaves out.

How it works

The standard base period is the first four of the last five completed calendar quarters before filing; the most recent completed quarter is skipped because employer wage reports lag behind. The tool derives those windows by date arithmetic alone, which is why it works for every state, and each state page adds its own agency wording about the alternate base period.

Getting the most from it

  1. Set the month and year you expect to file a claim.
  2. Read the highlighted quarters — those are the standard base period.
  3. Note the amber lag quarter, which many states add in an alternate base period.
  4. Check your state page to see whether its agency offers that alternate window.

Reading your result

The boundary is the useful part: a quarter with strong earnings sitting just outside the window may fall inside it a few weeks later, or drop out if filing is delayed. Read it as timing information, not as an eligibility rule.

What it can't tell you

It shows the common quarter structure, not state-specific variations such as extended base periods for illness or military service. Only the agency, using employer-reported wages, determines the base period actually applied to a claim.

Frequently asked questions

It is normally the first four of the last five completed calendar quarters before you file. The most recently completed quarter — the lag quarter — is skipped in the standard window because employers have not yet reported those wages to the state.

Part of: Unemployment benefits, state by state

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