Support Vessel Cost

A support vessel, or shadow yacht, is a second hull that runs alongside the mothership to carry the helicopter, chase boats, tenders, submersible, toys, and specialist crew that won't fit or shouldn't sit on the primary yacht. The capability is compelling. The cost is the part owners consistently underestimate, because a support vessel is not one bill but two: the price to acquire the hull, and the standing cost to run it as a fully crewed commercial-coded vessel for the life of the programme. This guide sets out both, qualitatively, across the 30 to 70m band where most of the market sits.

Buying one: conversion versus purpose-built

The first fork in the road is the biggest single driver of cost, and it is the choice between a purpose-built support yacht and a converted commercial vessel.

A purpose-built hull from a dedicated builder is engineered from the keel up as a yacht support platform. Damen Yachting's Yacht Support range, Astilleros Armon's Shadowcat hulls, Lynx Yachts, and the full-custom yards cover most of this market. You get a fast displacement or axe-bow hull, a proper helicopter facility, a designed garage and crane layout, and a finish that sits acceptably alongside the mothership. As a reference point for where values land, the 55m Damen support yacht Shadow was offered on the brokerage market at asking prices in the high teens of millions of dollars, and the 45.6m Pink Shadow asked just under fourteen million euros (Boat International). New build runs higher and rises steeply with length and capability.

The conversion route takes a laid-up offshore supply vessel or platform supply vessel, often available cheaply given the state of the offshore energy market, and refits it for yacht support. The result is robust, seaworthy, and capacious, and it can be delivered for a fraction of a new build, sometimes in single-digit to low-double-digit millions all-in. The trade is finish and flexibility: a converted OSV is industrial in its bones, the layout is constrained by the donor hull, and the work can still take two years or more. For an owner who values capacity over aesthetics, it is the most cost-effective way into the category. We cover the yards and platforms behind both routes at shadow vessel builders.

What drives the price

Once the route is chosen, four variables set the number.

• Size. Length is the master driver. A 35m support yacht and a 65m support yacht are different financial animals, and cost rises faster than length because larger hulls unlock helicopter hangars, wet garages, and longer-range autonomy that smaller hulls cannot carry. The support vessel sizes guide maps capability to length.
• Aviation. A touch-and-go pad is one cost. A certified hangar with aviation fuel, firefighting, and a refuelling system is a different order of money and reshapes the whole vessel. This is often the single most expensive capability decision, covered at helicopter support vessels.
• Submersible handling. A wet garage, launch system, and certified storage for a manned submersible add cost and crew, and tend to appear only on the larger hulls. See submarine support vessels.
• Specification and range. Ice-class plating for expedition support yachts, extended fuel and stores for global autonomy, redundant systems, and finish level all move the number before a single toy is loaded.

Running costs and crew

The acquisition price is the smaller surprise. The running cost is the larger one. A useful industry baseline is that a yacht costs around 10 percent of its capital value per year to run, and a support vessel behaves similarly, with crew as the dominant line.

Crew is where the support vessel earns its reputation as a standing commitment. It runs as a fully crewed working vessel with its own captain and engineering team, and the complement scales from roughly eight to twelve on a 45m hull up to the mid-twenties on a 75m. The specialists are the expensive part: helicopter pilot, engineer, and refueller; submersible pilot where carried; dive professionals; a deck team trained for crane work; and a medic on extended itineraries. Those are senior, certificated, and well-paid roles, and they are carried whether the vessel is working or sitting at anchor.

On top of crew sit fuel, dockage, classification and survey, insurance, and maintenance. The figure owners most often miss is that the helicopter and the submersible carry their own operating costs entirely separate from the vessel's. A serious 60m programme with active aviation and a chase-boat operation can run to several million euros a year all-in, before those aircraft and sub costs are counted.

A support vessel versus a chase boat, economically

The two assets solve different problems, and the cost gap between them is wide enough that the comparison usually answers itself.

A chase boat is a fast, independent day boat, typically 10 to 20m, run by a small dedicated crew. Its acquisition cost is a low single-digit million figure even for a bespoke flagship, and its running cost is a rounding error next to a support yacht's. It extends the speed and range of the day programme. It does not carry a helicopter, a submersible, or weeks of autonomous stores.

A support vessel is a different category entirely: a 30 to 70m commercial-coded ship whose whole purpose is to carry the heavy, noisy, capacity-hungry kit off the mothership and provide global margin. Its acquisition cost is an order of magnitude above a chase boat's, and its running cost is a recurring multi-crew commitment. The honest framing we use with owners is that a chase boat is a tool you buy; a support vessel is a programme you commit to. Many large yachts carry both, with the chase boat itself stowed aboard the support vessel. The full trade is set out at support yacht vs chase boat and from the smaller-vessel side at chase boat vs shadow vessel.

When the spend earns its place

The cleanest test is comparative. A support vessel earns its cost when the marginal spend on a separate hull is less than the marginal cost of building a bigger mothership to absorb the same load. For a 60m yacht that wants to add a helicopter, two chase boats, and a submersible, commissioning a 45 to 55m support yacht, or converting an OSV, is generally cheaper to build, easier to crew, and far more flexible than extending the mothership to 90m with all of that integrated. That arithmetic, more than any single price, is why the category exists and why values have held up across the brokerage market.

What we tell clients

Three things, in order. First, decide the route before you fall in love with a price: a conversion and a purpose-built hull of the same length are not competing on the same terms, and pretending otherwise leads to disappointment on both finish and budget. Second, build the running cost into the decision from day one, because crew and aviation are standing commitments that dwarf the purchase financing over a holding period. Third, let the toy load and the geography drive the size, not the other way around, because over-building a support vessel is the most expensive mistake in the category and under-building it sends the overflow straight back onto the mothership's deck.

If you are scoping a programme, start at the support vessels pillar and read across the capability spokes, then read shadow yachts for the operating model. When you are ready to put numbers against a real brief, that is the point to talk to us.