These are rules of thumb, not quotes. They are good enough to tell you whether a boat is affordable and useless as a budget you would hand a bank. Every figure below says where it came from, so you can replace it with a real number as soon as you have one.
| Each year | Low | High | Where the number comes from |
|---|---|---|---|
| Annual running cost |
- Per month
- Five years of running costs
- Five years including purchase
Why the 10% Rule Is Wrong at Both Ends
The rule everyone quotes is that a boat costs about 10% of its purchase price to maintain each year. It is a reasonable middle, and it misleads at both ends, in opposite directions.
The reason is that most of the work is priced by the foot, not by the value. Antifouling a 30-foot hull costs the same whether you paid $12,000 or $60,000 for the boat. Haul-out is quoted per foot. A rigging inspection takes the same afternoon either way.
So a cheap boat shows a frightening percentage, because a fixed cost is being divided by a small number. A large expensive boat shows a comfortable one, while the absolute figure is enormous. Neither owner is well served by the same 10%.
This calculator does two things instead. The percentage band moves with length, running higher for small boats and lower for large ones. Then a floor of $70 to $90 per foot per year is applied, taken from the invoice-level figures in our own sailboat upkeep breakdown, so a very cheap boat does not produce an impossibly small answer. Whichever is larger is the number shown.
Why Region Is an Input
Dockage is the line most likely to decide whether a boat is affordable, and it varies by three to five times across the United States. Quoting one national average would produce a number that is wrong almost everywhere.
| Where | Per foot per month |
|---|---|
| Inland and northern marinas | $12 to $30 |
| Mid-tier coastal | $15 to $35 |
| Premium coastal markets | $40 to $100 and up |
| Mooring, dry berth or trailer | $4 to $14 |
The same 35-foot boat can cost around $6,300 a year to keep at an inland marina and over $40,000 in a premium market. That is not a rounding difference, it is a different lifestyle. A mooring is the cheapest way to keep a boat afloat, at the cost of a dinghy ride every time you visit, and slip against mooring ball covers that trade properly.
What Actually Drives the Numbers Up and Down
Age, more than anything. A 1985 hull and a 2015 hull of the same length cost the same to berth and haul, and nothing like the same to keep running. Older boats are where deferred maintenance is hiding, and it surfaces on someone’s watch eventually.
Whether you do your own work. Yard labour is the single largest swing available to you. An owner who antifouls, services the engine and changes their own zincs saves a large fraction of the maintenance line every year.
Systems count. A watermaker, a generator, refrigeration, air conditioning and a bow thruster are all things that need servicing and eventually replacing. Two boats of the same length with different equipment lists are not comparable.
The big-ticket items that this table deliberately does not include. Standing rigging is commonly replaced on a cycle of roughly ten to fifteen years. Sails wear out. Engines get rebuilt or replaced. Each of those lands somewhere between one year and several years of running costs, and none of them arrives gradually. Setting money aside for them is what separates owners who are fine from owners who are surprised.
For the underlying figures rather than the rules of thumb, the average cost of buying and owning a sailboat has purchase price bands and worked examples, and sailboat insurance costs covers why the insurance line moves so much between boats. Registration and tax vary by state and are worth checking with the rest of the tools and the state-by-state registration guide before you commit.
Frequently Asked Questions
Common questions about running costs:
Does the First Year Cost More?
Almost always. A survey, registration and tax, and the jobs the survey finds all land in the purchase year. Budget a meaningful amount above the annual figure for the first twelve months.
Why Is There No Inflation in the Five-Year Total?
Because adding an invented inflation rate would make the number look more precise than it is. Treat the five-year figure as today’s money, multiplied.
Is Fuel Included?
No. On a sailboat fuel is usually small and depends entirely on how much you motor, so it is left out rather than guessed at. Add your own figure if you motor a lot.
Can I Really Halve This by Doing My Own Work?
You can take a large bite out of the maintenance line, which is usually the second largest. You cannot change dockage, insurance or the lift fee, so the total falls by less than people expect.
Does This Work for a Catamaran?
Treat it as a floor. Multihulls are usually charged one and a half to two times the monohull rate for a berth because of their beam, and haul-out needs a wider lift, which not every yard has.