Marine Wiring Cost for a Full Refit
Pull the headliner and the cabin panels off an older boat and you find out fast why a rewire scares people. Behind the vinyl is thirty years of add-ons: a stereo tapped off the nav-light circuit, butt connectors gone green, a bilge pump grounded to whatever screw was closest. The wiring “works,” right up until it doesn’t, and then you are asking what a proper refit really costs.
The short answer is a wide range, and anyone who quotes you a single number without seeing the boat is guessing.
So let me lay out honest dollars for a full 12V rewire, what actually drives the price up or down, and where you can spend less without cutting a corner that matters.
What a full 12V refit actually costs
A “full refit” means pulling the old wiring and starting clean: new positive and negative distribution, a fresh fuse or breaker panel, new runs to every light, pump, and electronic, and proper terminations at both ends. It is not patching one bad circuit.
The spread comes down mostly to boat size and who swings the crimper. A 17-foot center console has maybe a dozen circuits. A 38-foot cruiser can have sixty or more, plus AC shore power tangled in with the DC side.
Here is how the numbers tend to shake out in 2026 dollars. Parts figures assume tinned marine-grade wire and mid-tier panels, not the cheapest stuff on the shelf.
| Boat / scope | DIY parts only | Professional (parts + labor) | Rough hours |
|---|---|---|---|
| Small open boat (16-20 ft) | $400 to $1,200 | $2,500 to $5,000 | 25 to 45 |
| Mid cabin boat (22-28 ft) | $1,200 to $3,000 | $5,000 to $10,000 | 50 to 90 |
| Cruiser (30-40 ft) | $3,000 to $7,000 | $10,000 to $18,000+ | 90 to 160 |
Notice the gap between the DIY and professional columns. That whole difference is labor, and it is why this is one of the most rewarding jobs a handy owner can take on themselves.
The three things that drive the price
Strip away the details and three factors explain almost every dollar between a cheap refit and an expensive one. Get a handle on these and you can sanity-check any quote you are handed.
Boat size and circuit count
More circuits means more wire, more connectors, more panel positions, and far more hours. It is not linear either. Doubling the boat length can triple the wiring, because bigger boats carry AC systems, more pumps, and longer runs that need heavier gauge.
Longer runs also force you up a wire size to control voltage drop, the loss of voltage over a long cable that leaves lights dim and pumps sluggish. That is worth understanding before you buy a spool, and the plain-English version lives in Understanding Voltage Drop on Boats.
Labor: DIY or hired
A qualified marine electrician bills $90 to $150 an hour in most US markets, more in high-cost boating regions. On a mid-size boat that is easily 60 to 100 hours, so labor alone can run past $8,000.
That single line item is the whole reason the DIY route saves so much. If you can read a diagram and crimp a clean connector, you are buying back that entire number with your own weekends.
Parts quality
You can wire a boat for $400 in parts or $4,000, and the wire itself is a big part of the swing. Tinned copper wire, meaning each strand is coated in tin to fight corrosion, costs 20 to 40 percent more than bare copper and is the only thing that belongs on a boat.
Where the parts money actually goes
People picture the cost as “wire,” but wire is often less than a third of the bill. Here is where a typical mid-size parts budget really lands.
- Tinned marine wire: $300 to $900 depending on how much heavy gauge you need. Battery and inverter cables in 4-gauge, 2-gauge, or 1/0 are the expensive runs.
- Fuse or breaker panel: $120 to $600. A quality panel with labeled circuits is the heart of the job. If you are unsure which protection to run, Fuses vs Circuit Breakers on Boats lays out the tradeoffs.
- Bus bars, terminals, heat shrink: $150 to $400. Adhesive-lined heat shrink and quality ratcheting-crimp terminals are cheap insurance against the failures that send boats back to the shop.
- Fuses, breakers, switches: $100 to $300.
- Wire loom, clamps, labels, misc: $80 to $250.
Choosing the right gauge for each run is the one place a beginner most often overspends or, worse, underspends. The chart-and-table walkthrough in How to Choose Marine Wire Gauge keeps you from buying 10-gauge where 16-gauge would do, or the reverse.
Budget refit vs premium refit
Two boats can both get “rewired” and end up in very different places. The difference is not usually the wire. It is the panel, the labeling, and the terminations.
A budget refit uses solid tinned wire, a basic blade-fuse block, and clean crimps. It is safe, it works, and it might run $1,000 in parts on a small boat. There is nothing wrong with it.
A premium refit adds a breaker panel with individual switches, a proper battery switch and ACR, labeled runs at both ends, and often a battery monitor and bus-bar distribution that makes future work painless. That is where the extra thousands go, and on a boat you plan to keep, it earns its keep.
A real refit, and what it taught me about budget
A boat I rewired last spring was a 1998 24-foot walkaround the owner bought cheap, precisely because the electrics were a horror show. He wanted a number before I started, and I told him $2,400 in parts and about 55 hours.
The parts landed at $2,600, close enough. The hours ran to 70, because every time we opened a panel we found another surprise: a bilge pump wired straight to the battery with no fuse, a stereo amp grounded to a fuel-tank strap.
That overrun is the norm, not the exception. On any boat over fifteen years old, add 20 to 30 percent to your hour estimate for the mess you cannot see until you are in it.
The owner did his own labor with me coaching, and walked away having spent under $3,000 on a boat that now has a labeled breaker panel and not one automotive butt connector aboard. A shop would have charged him four times that.
Total cost of ownership, not just the install
The install bill is only part of the picture. A refit done right is also the cheapest thing you will ever do for the boat over ten years, because of what it prevents.
Corroded connections and undersized wire cause voltage drop, nuisance breaker trips, dead electronics, and in the worst case electrical fires, which the BoatUS Foundation consistently ranks among the leading causes of boat fires. A clean refit erases that whole category of expense and risk.
There is also resale. A buyer who opens your panel and sees labeled, tinned, fused circuits pays more and haggles less than one staring at a rat’s nest. I have watched a tidy electrical system add real dollars to a sale.
How to keep your refit affordable without cutting corners
You do not have to choose between cheap and safe. Most of the savings come from labor and planning, not from buying worse parts.
- Do the labor you can. Even pulling old wire and labeling runs before the pro arrives shaves billable hours. Labor is the big number.
- Buy wire by the spool, not the foot. Per-foot marine wire at the counter costs two to three times a 100-foot spool. Estimate generously and buy in bulk.
- Reuse what is genuinely good. A recent battery switch or a sound bus bar can stay. Rip out anything corroded or undersized.
- Plan every run before you buy. A wiring diagram on paper stops you from over-ordering heavy gauge or making a second parts run mid-job.
- Never economize on protection. Every circuit gets the right fuse or breaker at the source. That is not the place to save five dollars.
If this is your first serious electrical project, do not start with the whole boat. Get the fundamentals down first with the 12V Boat Wiring Guide for Beginners, then scale up to the full refit once crimping and fusing feel routine.
Spend on the bones, save on the labor
A full marine rewire is one of the few boat projects where doing it right and doing it affordably point the same direction. Good tinned wire, a proper panel, and clean fused terminations are not expensive in parts. The expense is hours, and hours are the thing a careful owner can supply.
Price your refit by the boat in front of you, not a number off a forum. Budget honestly for the surprises hiding behind the panels, protect every circuit, and label as you go. Do that, and the wiring you put in this season will outlast the boat, and you will never again wonder what that green crust under the dash is going to cost you.
Frequently asked questions
How much does it cost to rewire a boat?
It depends heavily on boat size and who does the labor. A small open boat runs $400 to $1,200 in DIY parts, or $2,500 to $5,000 with a professional. A 30 to 40 foot cruiser can reach $3,000 to $7,000 in parts alone, or $10,000 to $18,000 or more done by a marine electrician.
Is it cheaper to rewire a boat yourself?
Yes, and it is usually the single biggest saving available. Marine electricians bill $90 to $150 an hour, and a mid-size boat is easily 60 to 100 hours of work. If you can read a diagram and crimp a clean connector, doing your own labor buys back that entire number, often several thousand dollars.
What wire should I use for a marine refit?
Tinned copper marine wire, where each strand is coated in tin to resist corrosion. It costs 20 to 40 percent more than bare copper automotive wire but is the only thing that survives a salt environment. Automotive wire looks identical and corrodes from the inside out, which is what causes most green, crusty connections under a dash.
Why did my rewire cost more than the quote?
On any boat over fifteen years old, hidden problems are the norm. Pulling panels usually reveals unfused circuits, bad grounds, and old add-ons that all need fixing. Budget 20 to 30 percent more hours than your first estimate to cover the mess you cannot see until you are into the job.
Where should I spend the premium money in a refit?
Spend it on the distribution end, not the wire brand. A quality breaker panel with individual switches, labeled runs at both ends, and accessible bus bars saves hours every time you add or troubleshoot a circuit. The wire behind the panel is nearly the same whether the job is budget or premium.
