Massachusetts requires assessors to notify owners of the actual tax bill (not just assessed value) before the appeal clock starts. Abatement applications must be filed with the local Board of Assessors no later than the date the third-quarter (or first-half, in semiannual towns) tax bill is due — typically February 1. After Board denial or 3-month deemed denial, the appeal goes to the Massachusetts Appellate Tax Board (ATB) within 3 months. Massachusetts has Proposition 2½ limiting annual levy growth.
Verify before filing. Statutory deadlines change, and many counties operate on their own schedule inside the state framework. Always confirm the current year's window with the assessor or appeal board for the specific jurisdiction before relying on a date.
State-level deadlines plus major sub-jurisdictions where the schedule diverges from the state default. Where a column says "Varies," confirm the date with the local assessor.
| Month | Type | Event | Date | Details |
|---|---|---|---|---|
| January | RP | Lien date |
January 1 | Massachusetts assessment date — values set as of January 1 for the fiscal year beginning July 1. |
| January | RP | Q3 actual tax bill mailed (quarterly towns) |
By December 31 (mailed late Dec) | In quarterly-billing towns (most), the Q3 actual tax bill is the first bill showing the new assessed value. |
| February | RP | Abatement application deadline |
February 1 (or due date of Q3/first-half bill) | Abatement applications (Form 128) due to local Board of Assessors no later than the due date of the actual tax bill (typically Feb 1). |
| March | BPP | Form of List (Form 2) due |
March 1 | Personal property return required from businesses. Failure to file generally bars an appeal of personal property assessment. |
| Varies | RP | ATB petition deadline |
3 months from Board action | Petitions to the Appellate Tax Board (ATB) must be filed within 3 months of the local Board's denial (or deemed denial after 3 months of inaction). |
RP = Real Property · BPP = Business Personal Property · Both = Applies to both
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