Methodology
Every figure on Boston Units is computed in code from a verifiable source record. If a value cannot be computed from a source, it is left out. It is never estimated.
Sources
- Suffolk County Registry of Deeds, both the recorded land index and the registered land (Land Court) index, which are kept separately. masslandrecords.com/Suffolk
- City of Boston property assessment, FY2026, published on Analyze Boston. data.boston.gov
- MassGIS standardized assessor parcels, used for Chelsea, Revere and Winthrop. MassGIS Property Tax Parcels
Filters
- Market sales only
- The published record contains arm's-length market sales.
- Condominiums excluded
- Condominium unit transfers are excluded. The record covers whole buildings of 2 or more units.
- Nominal transfers excluded
- Deeds with stated consideration under $1,000 are treated as non-market transfers and are not published.
- Foreclosure and deed in lieu flagged
- Foreclosure deeds and deeds in lieu of foreclosure are published as events, flagged as distressed and excluded from per-unit price statistics.
- Portfolio sales flagged
- Where one instrument conveys several parcels to one grantee, the sale is published as an event, flagged as a portfolio sale and excluded from per-unit price statistics, because per-building allocations are usually not meaningful.
- Entity-to-entity transfers flagged
- Transfers between entities (for example LLC to LLC) are flagged for manual review before they are treated as market sales.
Tiers
| Tier | Units | Why the line is there |
|---|---|---|
| Small | 2–4 | Eligible for residential financing. |
| Mid | 5–20 | Commercial financing; typically valued on net operating income. |
| Large | 21+ | Lower volume, larger transactions. |
Pending verification: open assessor data reports unit counts as ranges for some buildings with 4 or more units, rather than exact counts. Tier assignment for those buildings is pending verification against building-level records and will not be published until it is confirmed.
Deeds excise cross-check
Massachusetts deeds carry a state excise based on consideration. The base rate is set by M.G.L. c.64D, §1. Including the 14% surcharge, the Department of Revenue states the rate in DOR Directive 95-4: “The rate of the excise (except for Barnstable county) is $2.28 per $500.00 of consideration (or fraction thereof) in excess of $100.00.” The Suffolk Registry's excise calculator uses the same rate. Where an excise amount is available, it is used to check the stated consideration mechanically.
What is not published
- Market predictions, interest rate commentary or investment advice.
- Any figure that cannot be traced to a source record.
- Descriptions of areas by the people who live there.
Corrections
If an entry is wrong, write to [email protected] with the address and book/page. Corrections are checked against the source record and noted.