A new 45 ft cruising catamaran in 2026 quotes at roughly €550,000–1,000,000 ex-VAT against €300,000–420,000 for a monohull of the same length, and it pays a published berth surcharge of 60–100% on top of the monohull rate. In exchange you get a 7.5 m platform instead of 4.5 m, a draft near 1.3 m instead of 2.1 m, and a boat that does not roll at anchor. You give up upwind performance, berth availability and simplicity of maintenance. The table below settles most of the argument; the sections after it cover the parts the numbers miss.
The numbers that decide the purchase
The comparison below uses a 44–46 ft production pair — a Fountaine Pajot Elba 45 against a Beneteau Oceanis 46.1 — because that is the size where most buyers actually cross-shop the two hull types.
| 45 ft catamaran | 45–48 ft monohull | |
|---|---|---|
| New price, 2026, ex-VAT | about €550,000–1,000,000 | about €300,000–420,000 |
| Beam | 7.55 m | 4.51 m |
| Draft | 1.32 m | 1.70 m shoal / 2.15 m deep |
| Displacement | 13,200 kg | 10,900 kg |
| Sail area | 100 m² | 95 m² |
| Marina berth | published multihull surcharge of 60–100% | standard rate |
| Pointing angle | 43–45° apparent | 38–40° apparent |
| Cabins and heads | 4 double, 4 heads | 3–5 double, 2–3 heads |
| Hull area to antifoul | roughly double | base |
Two figures from that table deserve a warning. First, the new-build price is the base price. A Lagoon 46 specified for charter delivery lands near €895,000 against an advertised base of about €687,000 — a 30% gap before anyone adds a watermaker. Second, the berth surcharge is not folklore. Ports de Monaco applies a flat 60% to every length band, Athens Marina applies 100% to any hull with a beam-to-length ratio above 0.35 in the 11–15 m band, and Marina Admiral in Opatija charges 70%. All three are published tariffs, not negotiating positions.
What the extra money buys on board
The space difference is structural, not cosmetic. A 45 ft catamaran carries a beam of 7.55 m against 4.51 m on a monohull that is a metre longer overall. That 3 m of extra width runs the full length of the boat, and it is what allows four double cabins each with its own head on the cat, where a monohull of the same length typically offers three cabins sharing two heads — and often a fourth cabin squeezed in only by shrinking the saloon.
Stability at rest is the other thing you are buying. A catamaran's two hulls sit 7 m apart, so the boat stays level in the chop that has a monohull rolling through 15–20° at anchor. If you have ever spent a night on a mooring listening to crockery move, you know what that is worth. It is also why catamarans dominate the Mediterranean charter fleet: guests who do not sail do not enjoy rolling.
If you are moving up from a smaller boat, the comfort question is worth separating from the hull-count question — a motor yacht will always be flatter and quieter still, at the cost of fuel and a much shorter range under its own power.
Where a monohull still wins
Upwind, and not by a small margin. A modern production monohull points at 38–40° to the apparent wind; a production cruising catamaran points at 43–45°, and the windward-leeward gap widens in a seaway because the cat has to be driven through waves rather than over them. On a 300-mile beat to windward, that difference is a day of your life.
The monohull also wins on everything to do with the berth. It fits a standard slip at the standard rate, and in the popular harbours that is not just cheaper but available — wide multihull berths are the first category to sell out and the last to be built. Annual berths for a 47 ft monohull in the Mediterranean run about €5,000–18,000 depending on the country, against €12,000–70,000 for a 14 m catamaran in Spain alone, where Palma and Ibiza berths are waitlisted for years.
Maintenance follows the same pattern. One engine instead of two, one saildrive, one set of through-hulls, one propeller to service. A monohull annual haul-out with wash and antifouling costs about €1,500–3,500. A catamaran presents roughly twice the wetted area, and Jolly Harbour in Antigua charges multihulls 57% more for antifouling than for storage of the same boat. Total running costs for a well-used 46 ft monohull land around €12,000–30,000 a year, berth included; add 20–40% for the catamaran equivalent. The full list is in our maintenance checklist.
Draft, anchoring and where the boat can actually go
A cruising catamaran draws 1.2–1.5 m with the boards up. A monohull of the same length draws 1.7 m in shoal-keel form and 2.1–2.2 m with a standard fin. That single number changes the cruising ground more than any other specification on this page: it is the difference between anchoring in a Bahamian bank at low water, nosing into a Caribbean beach, or spending the night on a mooring ball a mile offshore because the bay is too thin to enter.
It also opens up the smaller coves of a crowded cruising ground. If your plan is a summer working along the Mediterranean coast, the catamaran's draft lets you sit in anchorages that are empty because nothing else can get in — a point worth checking against our Mediterranean destination guide before you commit the extra purchase price to it.
Two safety notes to hold alongside each other. A catamaran is divided into watertight compartments and is very difficult to sink, but if one does invert in extreme conditions it tends to stay inverted. A monohull with a ballast keel self-rights from a knockdown. Neither is the safer boat in the abstract; they are different risk profiles, and which one suits you depends on the weather you intend to sail in.
Two of everything: the maintenance reality
A catamaran has two engines, two saildrives or shafts, two rudders, two fuel systems and two sets of sea cocks. Every one of those items is a service line, a spare part and a failure point. The engines themselves are usually smaller than a monohull's single unit, and a cat can often reach home on one, which is a genuine advantage — but the annual service bill is larger, not smaller.
Haul-outs are the practical trap. A 7.5 m beam needs a travel lift with a wide cradle, and outside the main refit yards that equipment may simply not exist. If your cruising plan includes remote islands, check which yards along the route can lift your boat before you buy it, not after. The same question applies at survey: an owner-version boat with one owner and a documented service history is worth the premium over an ex-charter hull with 1,500 engine hours on each of two engines.
Which one to buy
Choose the catamaran if you cruise with family or guests for weeks at a time, anchor more often than you berth, plan to spend seasons in thin tropical water, and can absorb a berth bill that is 60–100% higher than the monohull next to you. The interior volume and the flat ride are the product; everything else is the price of it.
Choose the monohull if the sailing itself is the point, if your passages include long beats to windward, if you want a boat that any yard in the world can lift and any marina can take, and if you would rather spend the difference on a better-equipped 45-footer than a base-spec catamaran.
Either way, three steps before you sign anything: confirm a berth is available and at what rate, get the hull surveyed by someone who has surveyed that specific type, and ask for the loaded weight — the numbers in the brochure are usually taken light. Our yacht survey guide sets out what to commission, and the full cost of ownership breakdown shows where the money goes beyond the purchase price.
Frequently asked questions
Is a catamaran more expensive to own than a monohull? Yes. Several Mediterranean marinas publish a flat multihull surcharge of 60–100% above the monohull rate for the same length band, a catamaran carries roughly twice the wetted hull area to antifoul, and it has two engines and two saildrives to service. Budget 20–40% more per year than a monohull of the same length.
Can one person handle a 45 ft catamaran? Docking is easier than on a monohull — the twin engines can be worked against each other to turn the boat in its own length. Sail handling is harder, because the loads on sheets and halyards are higher, so electric winches are near-essential above about 45 ft.
Do catamarans sail upwind as well as monohulls? No. A production cruising catamaran points at 43–50° to the apparent wind where a modern monohull of the same length holds 38–40°. Catamarans recover the difference off the wind, where the longer waterline and lighter displacement let them surf.
Which holds its value better? Volume-produced multihulls now hold value about as well as monohulls: Lagoon, Leopard and Fountaine Pajot have been retaining roughly 60–70% of value after five years. Buy the owner version rather than the ex-charter four-cabin layout — owner versions carry a 12–20% premium at resale.
Which is safer offshore? They carry different risks rather than different levels of safety. A catamaran is compartmentalised and very hard to sink, but if one inverts it tends to stay inverted. A monohull with a ballast keel rights itself from a knockdown, and a deep keel is a real asset in heavy weather as long as you accept the draft.
The right boat is the one whose costs you can live with for ten years, not the one that photographs best at the boat show. Start with the berth and the loaded weight, and the rest of the decision usually makes itself.