Generator repair costs $50 to $500 for a minor fix and $100 to $2,500 for a major malfunction, according to HomeGuide.[3] Scheduled maintenance is a separate line item: Angi puts a professional whole-house generator maintenance visit at $171 to $396, averaging $274, tying its 2026 national average to 1,488 verified projects from Angi Pros; corporate sibling HomeAdvisor publishes the identical average and range.[1][2]
Safety first: never run a portable generator indoors. The U.S. Consumer Product Safety Commission warns that one generator produces as much carbon monoxide as hundreds of cars and can kill in minutes. Use generators outside only, well away from windows, doors, vents and any other opening – never in a home, garage, basement, crawlspace or shed – and keep a working CO alarm in the house.[4]
Generator repair and maintenance cost by source
| Source | Average (per job) | Typical range (per job) | Scope as published |
|---|---|---|---|
| HomeGuide | (minor) $50 – $500; (major) $100 – $2,500 | (not listed) | Generator repair, split minor vs major |
| Angi | $274 | $171 – $396 | Whole-house generator maintenance per service visit; tied to 1,488 verified Angi Pros projects |
| HomeAdvisor | $274 | $171 – $396 | Whole-house generator maintenance per service visit |
These sources measure different jobs: HomeGuide publishes repair costs, while Angi and HomeAdvisor publish per-visit maintenance costs at their repair URLs. Angi and HomeAdvisor are corporate siblings, and matching figures alone do not establish independent corroboration. HomeGuide is a separate owner with separately published figures, and the pages state no shared sourcing.
Repair cost by repair type
| Repair type | Repair cost (HomeGuide, per repair) |
|---|---|
| Stator and rotor | $250 – $2,500 |
| Engine | $150 – $2,000 |
| Voltage regulator | $100 – $800, plus labor |
| Carburetor | $100 – $500 |
| Transfer switch | $50 – $400 (repair); $400 – $2,500 (replacement) |
Generator repair cost by repair type. Source: HomeGuide, which notes many repair technicians charge a minimum service call fee of $150 to $300 or more.
Repair cost by part
| Part | Repair cost (Angi & HomeAdvisor, per repair) |
|---|---|
| Stator and rotor | $250 – $1,500 |
| Engine | $50 – $2,000 |
| Carburetor | $60 – $500 |
| Voltage regulator | $80, plus the cost to hire an electrician |
| Transfer switch | $50 – $400 |
Generator part repair costs. Sources: Angi and HomeAdvisor, corporate siblings publishing the identical parts table. HomeAdvisor breaks transfer switch work down further: $50 to $200 for a repair, or $200 to $400 for a replacement plus three to four hours of electrical labor. HomeGuide publishes different ranges for several of the same components (stator and rotor $250 to $2,500, carburetor $100 to $500, engine $150 to $2,000, voltage regulator $100 to $800); each publisher’s figures are reported with its own page, and the pages state no shared sourcing.
Maintenance cost by generator type
| Generator type | Annual maintenance cost (HomeGuide, per year) |
|---|---|
| Portable | $50 – $150 |
| Propane | $200 – $600 |
| Natural gas | $200 – $650 |
| Gas or diesel | $200 – $1,000 |
| Engine-driven (30 to 45 kW) | $350 – $600 |
Annual generator maintenance cost by type. Source: HomeGuide. Angi and HomeAdvisor publish per-type maintenance figures too – portable at $50 and large or standby engine units at $600 on average – and HomeAdvisor’s own page disagrees with itself on annual upkeep: its summary says $85 to $720 while its prose says $200 to $600 per year. All versions are reported as published.
Add-on and replacement costs
Angi prices common add-ons: installing a generator transfer switch runs $400 to $2,500, installing a circuit $570 to $1,000, installing a subpanel $400 to $1,750, wireless monitoring $200 to $400, and a backup battery $10,000 to $25,000.[1] When a generator is beyond repair, HomeGuide puts a new portable generator at $900 to $3,800 installed and a whole-house generator at $6,000 to $11,000.[3]
Safety: carbon monoxide and electrical work
Carbon monoxide is the reason placement rules are absolute: the CPSC warns that generator exhaust is a poison you cannot see or smell, that one generator produces as much CO as hundreds of cars, and that running one indoors can kill in minutes. Portable generators belong outside only, far from windows, doors and vents, and every home using one needs a working CO alarm.[4]
On the electrical side, a transfer switch connects the generator to your home’s electrical circuit.[3] HomeAdvisor prices the job as electrical labor – three to four hours for a replacement – and pairs its voltage regulator figure with the cost to hire an electrician.[2] Because the hazards are carbon monoxide, fuel and household wiring, this guide leaves procedures to the unit’s own manual and licensed professionals, and carries no shopping link.
Related cost guides
See our guides to whole house generator cost, generator installation cost, electrical panel upgrade cost, sump pump battery backup cost and furnace repair cost.
Sources
- Angi – Whole-House Generator Maintenance Cost (updated Sep 18, 2026; maintenance-labeled figures published at Angi’s generator repair cost URL)
- HomeAdvisor – Whole-House Generator Maintenance Cost (updated Jun 19, 2026; maintenance-labeled figures published at its repair-a-generator URL)
- HomeGuide – Generator Repair and Maintenance Cost (updated Jan 14, 2026)
- U.S. Consumer Product Safety Commission – Generators and Engine-Driven Tools (federal CO safety guidance)