Interior tenant fit out of the 3rd and partial 10th floors for Klaviyo with communicating stair on 4th and
Alteration or repair at 125 Summer St, Boston
Boston Inspectional Services Department permit ALT1749165: issued Aug 22, 2025 for alteration or repair work at 125 Summer St. Interior tenant fit out of the 3rd and partial 10th floors for Klaviyo with communicating stair on 4th and 5th floor. Approximately 20,000 sq ft. Work to include; new office, communicating stair, lighting, millwork, paint, flooring, finishes and sprinkler and FA modifications.
- Permit number
- ALT1749165
- Issued
- Type of work
- Alteration or repair
- Status
- Finished
- Reported cost
- $3,522,800
- ZIP code
- 02110
- City's category
- Fast Track Application, Long Form/Alteration Permit
- City's status
- Closed
- Source
- Boston Inspectional Services Department permit data (this record)
Type of work and status are our own standard labels, so permits compare across cities. The city's wording is in the "City's category" and "City's status" rows. We show costs under $100 as not listed, because filers often enter $0 or $1 when the city doesn't require a cost.
All permits at 125 Summer St, and what's permitted nearby
Boston Inspectional Services Department updated its data Oct 5, 2026. We checked it Oct 6, 02:58 UTC. See the city's official records.
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