# M.J. Carr Electrical Services, LLC

**Trade:** Electrical · **Address:** 440 Plain St Ste 4A, Marshfield, MA 02050, USA · **Phone:** (781) 527-5105 · **Website:** https://www.mjcarrelectricalservices.com/ · **Languages:** English

**Rating: 4.1/5** (medium confidence) — from 109 reviews across 5 sources.
100% of sentiment-scored reviews read net-positive. Last 6 months: 4 reviews, 0 negative.

## The honest read

M.J. Carr Electrical Services works out of Marshfield, and the specifics in its reviews cluster around two kinds of jobs: panel upgrades and generator hookups. Reviewers describe 100-to-200-amp service upgrades handled start to finish -- permits pulled, town inspections coordinated, the National Grid cutover scheduled -- rather than a quick swap.

On the generator side, a 2026 review says the crew 'sent over a full list of instructions' on starting a generator during a storm, while another describes Tim installing a manual transfer switch for a portable unit. In a 2022 review, a customer wrote the crew 'took the time to walk me through' a new generator, then came back the following year to install recessed lighting and add outdoor hookups.

The company also wires EV chargers -- one customer had a charger and a floodlight camera installed in the same visit, another paired a car charger with circuit-breaker work -- and runs dedicated circuits for larger appliances. When something's actually wrong, the diagnostic work reads as careful rather than rushed: in a 2024 review, technician Sawyer traced a 'perplexing' circuit-breaker complaint through several possible causes before ruling the breaker itself fine, and on an earlier visit the same technician arrived with two solutions already worked out.

Google shows 174 ratings averaging five stars, and the Better Business Bureau grades the company A. The reviews run from 2021 through this year, with four more landing in just the past six months and none of them negative. In a 2023 review, one customer wrote they'd been using the company 'for many years' and the job was 'always done right', and a handful of others -- Tim, Jeff, Sawyer, Jen in the office -- turn up across multiple projects.

The one thing worth flagging: in a 2025 review, a customer called the company 'expensive, but... worth the no worry' -- nobody else raised cost as an issue, so it reads as one person's take on where they sit in the market rather than a pattern. For a panel upgrade, a generator hookup, or an EV charger install, this is a company with a long paper trail of doing exactly that kind of work cleanly; worth pinning down the estimate up front given that one note on price.

**Strengths:**
- Panel upgrades — 100 to 200 amp, permits and inspections handled
- Generator hookups — transfer switches and clear customer walkthroughs
- EV charger installs — paired with dedicated circuits and lighting work
- Careful diagnostics — traces breaker issues before swapping parts

**Concerns:**
- Pricing — one customer called it expensive despite good results

## Claims & citations

Every claim below is backed by real evidence rows — uncited claims are dropped in code before publication.

- Handles 100-to-200-amp panel upgrades including permitting and town/utility coordination _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNZMUtUUHhBRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCY1KTPxAE%7C%7C?hl=en) — “5★ Thank you very much for the amazing work your team completed for our relocation and upgrade to 200amp service for our house; including bu…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnTUN3NDZLOFFnEAE!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCw46K8Qg%7C%7C?hl=en) — “5★ My experience with M.J. Carr electrical was excellent.
They were prompt and professional from the quote to the conclusion.
The electricia…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNnc3NLUG9RRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCgssKPoQE%7C%7C?hl=en) — “5★ I live in Hingham, and i have used the service of MJ Carr twice! Once in the summer, when they upgraded the amps of the house from 100 to…”
- Installs and explains generator hookups and transfer switches _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSUQtb0xtWWpnRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgID-oLmYjgE%7C%7C?hl=en) — “5★ Friendly, an efficient service! They took the time to walk me through what they did and how to use my new generator. I also really like t…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sCi9DQUlRQUNvZENodHljRjlvT201MFpWcGZhbTlxTjJkTlRtUklSMDFQVWt4V1dYYxAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CAIQACodChtycF9oOm50ZVpfam9qN2dNTmRIR01PUkxWWXc%7C%7C?hl=en) — “5★ Extremely helpful with insight on how to get my generator started. Sent over a full list of instructions based on the model. Could not be…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSURObGRYUlZ3EAE!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIDNldXRVw%7C%7C?hl=en) — “5★ Great service and good quality work. Tim installed a manual transfer switch for my portable generator. Would recommend this team to anyon…”
- Wires EV chargers and dedicated circuits for major appliances _(confidence: medium)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSURuOUo2RG9BRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIDn9J6DoAE%7C%7C?hl=en) — “5★ I cannot recommend M.J. Carr Electical Services enough!  Fantastic communication, great work, and friendly and respectful people.  This w…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNnc3NLUG9RRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCgssKPoQE%7C%7C?hl=en) — “5★ I live in Hingham, and i have used the service of MJ Carr twice! Once in the summer, when they upgraded the amps of the house from 100 to…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSUM3eXVHbDh3RRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIC7yuGl8wE%7C%7C?hl=en) — “5★ MJ Carr installed dedicated lines for me. They were pros and made it look easy.”
- Careful circuit-breaker diagnostics rather than a rushed panel swap _(confidence: medium)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSUQ3cXNMUXN3RRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgID7qsLQswE%7C%7C?hl=en) — “5★ M.J. Carr Electrical Services as usual were outstanding. Matt showed up to assess our Situation and quickly came up with 2 viable solutio…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSURMbDZTNzlRRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIDLl6S79QE%7C%7C?hl=en) — “5★ We asked M. J. Carr to look at a perplexing problem we were having with a circuit breaker. Sawyer the technician they sent, made a detail…”
- Repeat customers report years of consistent, reliable work _(confidence: medium)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSUNabGR6eWJREAE!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgICZldzybQ%7C%7C?hl=en) — “5★ Matt Carr & his team continues to offer very responsive, professional & reliable service.  I highly recommend them.”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSUNubVlfZXl3RRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgICnmY_eywE%7C%7C?hl=en) — “5★ I have been using MJ Carr for many years and theya are extremely reliable and the job is always done right.
Highly recommend.”
- Better Business Bureau grade: A _(confidence: high)_
  - [Better Business Bureau](https://www.bbb.org/us/ma/marshfield/profile/electrician/mj-carr-electrical-services-llc-0021-558889) — “Better Business Bureau grade: A”
- Google rating of 5 stars from 174 ratings _(confidence: high)_
  - [Google](https://maps.google.com/?cid=15459361678342769712&g_mp=CiVnb29nbGUubWFwcy5wbGFjZXMudjEuUGxhY2VzLkdldFBsYWNlEAIYBCAA) — “Google: 5★ from 174 ratings”
- One customer described pricing as expensive, though worth it for reliability _(confidence: low)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTURBa3ZHWTZBRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMDAkvGY6AE%7C%7C?hl=en) — “5★ They come on time. They give a one hour window. They know what they are doing. Yes they are expensive, but it’s worth the no worry”
- Electrical panel upgrades _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNZMUtUUHhBRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCY1KTPxAE%7C%7C?hl=en) — “5★ Thank you very much for the amazing work your team completed for our relocation and upgrade to 200amp service for our house; including bu…”
- Generator installation and hookup _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSUQtb0xtWWpnRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgID-oLmYjgE%7C%7C?hl=en) — “5★ Friendly, an efficient service! They took the time to walk me through what they did and how to use my new generator. I also really like t…”
- EV charger installation _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNnc3NLUG9RRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCgssKPoQE%7C%7C?hl=en) — “5★ I live in Hingham, and i have used the service of MJ Carr twice! Once in the summer, when they upgraded the amps of the house from 100 to…”
- Circuit breaker diagnostics and repair _(confidence: medium)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSURMbDZTNzlRRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIDLl6S79QE%7C%7C?hl=en) — “5★ We asked M. J. Carr to look at a perplexing problem we were having with a circuit breaker. Sawyer the technician they sent, made a detail…”
- Dedicated circuit installation _(confidence: medium)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSUM3eXVHbDh3RRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIC7yuGl8wE%7C%7C?hl=en) — “5★ MJ Carr installed dedicated lines for me. They were pros and made it look easy.”
- Specializes in Electrical _(confidence: high)_
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNZMUtUUHhBRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCY1KTPxAE%7C%7C?hl=en) — “5★ Thank you very much for the amazing work your team completed for our relocation and upgrade to 200amp service for our house; including bu…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnTUNnc3NLUG9RRRAB!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgMCgssKPoQE%7C%7C?hl=en) — “5★ I live in Hingham, and i have used the service of MJ Carr twice! Once in the summer, when they upgraded the amps of the house from 100 to…”
  - [Google Reviews](https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSURObGRYUlZ3EAE!2m1!1s0x0:0xd68aaf8a0be84c30!3m1!1s2@1:CIHM0ogKEICAgIDNldXRVw%7C%7C?hl=en) — “5★ Great service and good quality work. Tim installed a manual transfer switch for my portable generator. Would recommend this team to anyon…”

## License

Status: **not_found** — verified against the official MA state registry, never self-reported.
Re-check at the official registry: https://elicensing21.mass.gov/CitizenAccess/GeneralProperty/PropertyLookUp.aspx?isLicensee=Y&TabName=Home

## Sources

- [Google](https://www.google.com/maps/search/?api=1&query=M.J.%20Carr%20Electrical%20Services%2C%20LLC&query_place_id=ChIJI31pQyKf5IkRMEzoC4qvitY): 5.0★ from 174 ratings
- [Google Reviews](https://www.google.com/maps/search/?api=1&query=M.J.%20Carr%20Electrical%20Services%2C%20LLC&query_place_id=ChIJI31pQyKf5IkRMEzoC4qvitY): Listed on this source
- [Better Business Bureau](https://www.bbb.org/us/ma/marshfield/profile/electrician/mj-carr-electrical-services-llc-0021-558889): Listed on this source
- [Official Website](https://www.mjcarrelectricalservices.com): 20 yrs in business · Self-reported profile and service details
- [Exa](https://reviews.birdeye.com/mj-carr-electrical-services-llc-166925749274905): 5 web mentions across the open web (each linked to its source)

## Recent reviews

- **5/5 · Google Reviews · Greg Tsinzo · 2026-04-09**: Instant response, easy booking, great Job!
- **5/5 · Google Reviews · Bo Belanger · 2026-04-09**: These guys were fantastic! On time, very professional. Would highly recommend.
- **5/5 · Google Reviews · Lucinda Vanderweil · 2026-03-04**: Easy to schedule appointments, professional and knowledgeable electricians who stand by their work.  Would highly recommend.
- **5/5 · Google Reviews · Courtney McNulty · 2026-03-02**: We love MJ Carr and all the work we get from them. They are our go to electricians and we have had pleasant experiences with every technician that has come out. Can’t recommend them enough!
- **5/5 · Google Reviews · Steve Sheldon · 2026-01-28**: Great work. Fast, efficient and all on the tail end of a huge snow storm and sub zero weather.  M.J. Carr helped get my furnance up and running on short notice.
- **5/5 · Google Reviews · James Tasca · 2026-01-24**: Extremely helpful with insight on how to get my generator started. Sent over a full list of instructions based on the model. Could not be more thankful and highly recommend Matt.
- **5/5 · Google Reviews · Mary Gentile · 2025-09-01**: Excellent customer service in all aspects.  Couldn’t be more pleased with the work that was done.
- **5/5 · Google Reviews · Doreen Sullivan · 2025-08-12**: I highly recommend MJ Carr Electrical Services.  Excellent work, fair pricing and prompt service.  Replaced my exterior outlets and light switches.   Super nice and professional
- **5/5 · Google Reviews · Iron Foot Co · 2025-07-22**: MJ Carr continues to provide amazing service for all our needs. We love working with them.
- **5/5 · Google Reviews · David Gavin · 2025-06-09**: On time, pricing was where I thought it would be and cleaned up perfectly after they finished.

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Data freshness: last scanned 2026-07-05T11:29:05.682Z.
Cite as: M.J. Carr Electrical Services, LLC — Tavlee (https://tavlee.com/contractor/m-j-carr-electrical-services-llc-marshfield)
Source: https://tavlee.com/contractor/m-j-carr-electrical-services-llc-marshfield