Catamaran vs Monohull

The Beam Surcharge Is Published, Not Anecdotal

The commonly repeated claim that catamarans pay one and a half to two times monohull berthing rates is one of the few pieces of yachting folklore that survives contact with primary documents. Four marinas across three jurisdictions publish the surcharge explicitly, and the range they describe is tight.

Monaco applies a flat sixty per cent uplift to every band 1. On a vessel between 15.00 and 15.99 metres, where the monohull rate is €2,834.40 per month in high season including VAT, the catamaran pays €4,535.04. In low season the monthly rate moves from €1,417.20 to €2,267.52. Because the surcharge is applied to the tariff rather than to a beam measurement, a narrow performance catamaran and a wide charter platform pay identically.

Athens Marina goes further and prices the surcharge at one hundred per cent, but reaches it by a different route. The uplift applies to vessels with more than one hull, or to other types whose features modify the conventional length to beam ratio, and the trigger is stated numerically: a beam to length ratio above 0.40 for vessels up to ten metres, above 0.35 for eleven to fifteen metres, above 0.30 for sixteen to twenty-five metres, and above 0.22 above that 2. Nearly every production cruising catamaran breaches those thresholds comfortably. A fifteen metre catamaran therefore moves from the published annual rate of €14,670 to €29,340 before twenty-four per cent Greek VAT. Two provisions on the same card compound the effect for anyone not committing to a full year: alongside mooring carries a further hundred per cent, and any stay of ninety days or less is charged at one three hundred and sixty-fifth of the annual rate increased by a further hundred and ten per cent per day 2.

Marina Admiral in Opatija, whose tariff took effect on 1 August 2026, prices catamarans at seventy per cent above the monohull rate 3. A fifteen metre annual berth costs €9,750 including VAT, water, sixteen amp power and marina liability insurance, so the catamaran equivalent is €16,575. The card carries a second and separate provision: for vessels exceeding the beam specified for their length band, an extra charge of fifty per cent of the berth price applies. The band for fifteen metres allows 4.79 metres of beam, which almost no cruising catamaran of that length respects. The document sets out the two provisions independently and does not state whether they are applied cumulatively, so the honest reading is that the catamaran pays at least €16,575 and possibly considerably more.

In the Caribbean, Jolly Harbour in Antigua publishes two complete and separate rate cards, which makes it the cleanest like for like comparison in the public domain. On the winter card, running 1 November to 31 May, a monohull pays $1.45 per foot per day daily and $1.00 on the quarterly rate; the catamaran pays $2.45 and $1.70 4 5. The implied premium is remarkably consistent across every cell: sixty-nine per cent on winter daily, seventy per cent on winter quarterly, sixty-eight per cent on summer daily. Even the mooring buoys carry it, at $50 a night against $35. For a fifty foot vessel taking a winter quarter, that is $7,650 against $4,500 before government taxes and metered utilities, a difference of $3,150 for ninety nights.

The mechanism is worth stating because it explains why the surcharge is unlikely to erode. A marina sells water surface and pontoon frontage, not length. A twelve metre wide catamaran occupies the space of two monohulls and requires a berth configuration that cannot be resold to a monohull without waste. The premium is not a penalty for owning the wrong boat. It is the correct price of the space consumed, which means it is structural.

The Yard Charges for Complexity, Not Length

Haul-out and hard standing produce a smaller premium than berthing, and a more interesting one, because the two Jolly Harbour boatyard cards are itemised service by service and the surcharge is not uniform across them.

On the headline operation, hauling, pressure washing, launching and chocking, the monohull rate is $17.75 per foot and the catamaran rate $24.20, a premium of thirty-six per cent 6 7. Storage follows closely: $19.75 per foot per month against $26.50, thirty-four per cent, and $17.65 against $23.95 on the long term rate with a three month minimum, thirty-six per cent. But the wet work diverges further. Pressure washing weed slime costs $3.15 per foot on a monohull and $4.95 on a catamaran, fifty-seven per cent more, and scraping barnacles $3.25 against $4.95, fifty-two per cent more.

That divergence is informative. Lifting and storing a catamaran costs roughly a third more because it needs a wider travelift and more yard footprint. Cleaning and painting one costs half as much again because two hulls have substantially more wetted surface than one hull of the same length, and because the bridgedeck and inboard hull faces are awkward to reach. Antifouling is not a length-driven cost, and any comparison that scales it by length will understate the catamaran by a wide margin.

Both cards carry an identical escalator that is easy to miss and expensive to discover: boats forty-five feet and over pay an additional fifteen per cent, and boats sixty feet and over an additional thirty per cent 6 7. Crossing forty-five feet triggers a published surcharge on every yard service, on both hull types. Worked through, a fifty foot catamaran hauled, washed, launched and chocked pays $24.20 multiplied by fifty feet and by 1.15, which is $1,391.50, against $1,020.63 for a fifty foot monohull. Six months on the long term storage rate costs the catamaran $7,185 and the monohull $5,295, a difference of $1,890 per season on that line alone.

There is a constraint behind the pricing that matters more than the pricing. Jolly Harbour's catamaran haul-out and storage facility only opened in May 2024, and it accommodates catamarans up to seventy-five feet in length and thirty-three feet in beam 5. That is a hard physical ceiling published by the yard, not a commercial preference. Catamaran-capable lifting infrastructure remains scarce relative to the size of the catamaran fleet, and a vessel that exceeds the local travelift's beam capacity has no economic answer other than to move, at delivery cost, to a yard that can take it. Scarcity of infrastructure is a real cost even in the years it is not billed, because it removes the owner's ability to shop.

The Sail-Away Price Is Thirty Per Cent Above the Sticker

The acquisition side of the comparison suffers from a different problem: the advertised price of a new catamaran is not a price anyone pays. Lagoon publishes an indicative retail price list for the Lagoon 46, dated September 2025 for the A2026 model year, and it is unusually complete because it itemises delivery separately from equipment 8.

The base boat, in three cabin configuration with three heads and twin fifty-seven horsepower Yanmars, is €686,800 excluding VAT. That is the number that appears in advertising. The Iconic equipment pack, which bundles the essential and comfort equipment with the navigation package, adds €109,885. Air conditioning is €36,300 and a generator €31,000, both of which are effectively mandatory for any vessel intended for warm-water charter. Delivery is priced as a separate line: transport, launch and rigging with antifouling is €23,700, a four day handover is €3,900, and papers and registration documents are €3,000 8.

Those seven lines total €894,585 excluding VAT, or thirty per cent above the advertised base price, and the resulting vessel still has no watermaker, no tender, no solar array and no lithium bank. The same list prices a hundred litre per hour watermaker at €15,290, a hydraulic tenderlift at €46,300 and a furling boom at €38,130 8. A realistically specified charter catamaran of this size clears €950,000 before tax without difficulty.

This matters for the comparison in a specific way. Every operating premium quantified above, sixty to a hundred per cent on the berth and thirty-five to fifty-five per cent in the yard, is applied to a cost base that is itself larger. The premiums do not compare a €700,000 catamaran to a €700,000 monohull. They compare a €900,000 catamaran to a monohull that would typically be bought at a materially lower price for the same length, and then charge it more each year to keep. The compounding runs in one direction.

It also complicates any depreciation comparison, and here the honest answer is that no comparison is available. There is no publicly published, independently compiled residual value series specific to catamarans. Broker marketing regularly cites strong five year retention figures for popular production models, but those figures trace to single brokerage sites with a direct commercial interest and no stated methodology. They should be treated as advertising until someone publishes the data behind them. What can be said with reference to independent pricing data is general and applies to both hull types: boats follow an S-curve, larger boats depreciate more slowly than smaller ones, and insurability restrictions at the twenty, twenty-five and thirty year marks tend to re-accelerate the decline late in life. None of that is catamaran-specific, and pretending otherwise is where most comparisons of this kind go wrong.

Why the Yards Switched

If catamarans cost more to buy and more to keep, the interesting question is why production has moved so decisively towards them. The answer is in the builders' accounts rather than the owners'.

The Fédération des Industries Nautiques presented figures at its annual general meeting on 31 March 2026 covering the nautical year from September 2024 to August 2025. Multihulls accounted for 1,019 of 2,373 French sailboats built, forty-three per cent by unit. They accounted for €759.2m of €1.02bn in sailboat revenue, seventy-four per cent by value. More strikingly, multihulls now represent fifty-one per cent of all French boatbuilding revenue, sail and motor combined, from dinghies to superyachts 9.

Divide those figures and the mechanism becomes obvious. Yard revenue per unit was €745,000 for a sailing multihull against €195,000 for a sailing monohull, a ratio of 3.8 to one 9. These are yard revenues rather than retail prices, so they sit below sticker, but the ratio is the point. A builder that converts a production line from monohulls to catamarans roughly quadruples the revenue that line generates from the same floor space and broadly the same labour force. That is not a response to demand so much as an industrial reallocation towards a higher price point, and it explains the shape of the new-boat market far better than any argument about sailing characteristics.

The same dataset shows the segment held up better through the post-pandemic correction. In 2024 to 2025, sailing monohull revenue fell thirty per cent while sailing multihull revenue fell nineteen per cent; motorboats under nine metres fell eighteen per cent and motorboats over nine metres only three per cent 9. The pattern is consistent and it is about price points rather than hull configuration. The segments serving the most discretionary, most credit-sensitive buyers fell hardest. Catamarans sit further up the wealth distribution and were correspondingly more insulated.

For an investor, the implication cuts both ways. Relative resilience in a downturn is a genuine attribute and it is measured here rather than asserted. But the same data shows that the buyer is funding a structural repricing of the product. Paying €745,000 of yard revenue per unit instead of €195,000 buys more boat, and it also buys into a segment whose economics depend on the higher price point being sustained.

The Revenue Case Is Asserted More Than It Is Evidenced

The standard rebuttal to everything above is that catamarans earn more. They command higher weekly charter rates, they achieve higher occupancy because they carry more guests in more comfortable accommodation, and the revenue premium more than compensates for the cost premium. This is stated with great confidence across the industry and it is almost certainly directionally true. It is also, in the public record, essentially unevidenced.

There is no independently published dataset giving catamaran charter rates against comparable monohull rates by region and season, and no published occupancy series distinguishing the two. Charter fleet operators hold this data and do not release it. Brokerage sites publish rate premiums without methodology, sample size or the definition of a comparable vessel. Anyone underwriting a catamaran on the assumption of a specific revenue premium is underwriting on a number that has not been published, which is a materially different position from underwriting the cost side, where four marinas and one yard have published their tariffs in full.

That asymmetry should change how the comparison is read. The costs above are known with reasonable precision: sixty to one hundred per cent on the berth, thirty-four to fifty-seven per cent in the yard, thirty per cent between advertised and sail-away price. The offsetting revenue is estimated. Underwriting a known premium against an estimated one is not a neutral exercise, and the conventional presentation, in which the revenue advantage is assumed and the cost premium is mentioned in passing, has the epistemics precisely backwards.

Three further considerations argue against a reflexive preference for two hulls. Beam capacity is a binding physical constraint in many cruising grounds, and the operator who cannot haul locally has lost the ability to negotiate. The berthing surcharge falls hardest in exactly the ports that command the highest charter rates, so the cost premium and the revenue premium tend to be co-located rather than offsetting. And no residual value series exists to test the resale half of the argument at all.

Above all, both hull types face the same hurdle, and it is not each other. A liquid government bond currently offers a positive real return with no berth, no travelift, no antifoul cycle and no charter season. Any marine asset, of any configuration, has to clear that after operating costs, management fees and depreciation before the comparison between one hull and two becomes worth having. Capital deployed against these assets is at risk, and any return discussed in this market is a target rather than a commitment.

Where the Answer Actually Turns

The honest conclusion is conditional, and the condition is the cruising ground rather than the vessel.

In the Caribbean, the case for two hulls is strongest. Charter itineraries are short, anchorages are the norm and marina nights are the exception, so the sixty to one hundred per cent berthing surcharge applies to a small fraction of the season. Shallow draught opens anchorages a monohull cannot use. The yard premium of roughly thirty-five per cent on lift and storage is real but is incurred once or twice a year, and at Jolly Harbour it amounts to something in the order of $1,890 a season on storage plus $371 on the haul itself for a fifty foot vessel 6 7. Against a season of charter revenue, those are manageable numbers.

In the Mediterranean the arithmetic inverts. Med-mooring is the dominant berthing mode, marina nights are frequent rather than exceptional, and the surcharge falls on almost every night of the season. Athens at one hundred per cent, Monaco at sixty and Opatija at seventy are the ports the itineraries actually visit 1 2 3. A vessel that spends most of its season alongside is paying the beam premium continuously, and it is paying it on a hull that cost roughly thirty per cent more than its advertised price to put in the water. For a Mediterranean programme with heavy marina use, a well specified monohull can be the better underwriting decision even where the catamaran achieves the higher day rate, and the burden of proof sits with anyone claiming otherwise.

Between those poles, the decision turns on inputs the individual buyer usually cannot obtain. What is the actual occupancy differential in this cruising ground, this season, at this size. What does the local yard charge for a beam this wide, and can it lift the boat at all. What proportion of nights will realistically be spent alongside rather than at anchor. These are fleet-level questions. They are answerable with fleet-level data, and they are close to unanswerable for a single owner buying a single boat on a broker's spreadsheet.

That asymmetry is the argument for professionally operated structures generally, and it is the observation HelmShare is built around. HelmShare Prime Fund, L.P., a Cayman Islands Exempted Limited Partnership with HelmShare LLC (DIFC) as General Partner and Investment Manager, holds a professionally operated charter fleet in which hull configuration is an underwriting variable set against measured utilisation rather than a lifestyle preference set at the boat show. Interests are offered under Regulation S outside the United States to professional, qualified and high net worth investors. It is one structural response to the data problem described above, and it does not make the data problem disappear; it moves it to a party with the fleet to measure it.

The open question is whether the catamaran premium survives its own success. Marinas price beam because beam is scarce. If the multihull share of the fleet continues to rise at the rate the French production data implies, either marinas will reconfigure to accommodate it, in which case the surcharge compresses, or they will not, in which case the surcharge rises and the constraint binds harder. Both outcomes are plausible, they point in opposite directions for the same asset, and nobody in this industry is currently publishing the data that would tell an investor which is happening.