Dolphin 31 Buyer's Guide
Shopping the brokerage market for a used Dolphin 31 means looking at a John B. Sharp masthead sloop of the late 1970s, built by Carlisle & Williams and later Offshore Yachts, with a modest production run that keeps any example a relatively uncommon sight. She was drawn with the charter trade in view, and though that ambition only partly paid off, many left as private cruising boats and remain straightforward, repairable candidates for a first cruiser.
Layouts on the Used Market
The boat sleeps six, and the used fleet generally preserves the original arrangement: a dinette that folds to a double, an unusual twin quarterberth stacked in two tiers, a large galley for the period, and a well-proportioned forecabin. Teak interiors are standard. Because she was built with charter use in mind, the accommodation plan tends to be practical rather than bespoke, and buyers should expect a cruising layout that has worn according to each owner's care rather than a stripped racer.
Equipment and Common Upgrades
No single equipment list covers every boat, so buyers should assess each one on its own merits. The most consequential items to verify are those tied to the masthead rig and ground tackle: the original spec calls for 31-foot jib and genoa sheets and a 77.5-foot mainsheet in half-inch diameter, with a 68.2-foot spinnaker sheet—confirm that running rigging has been renewed to those lengths and sizes, as worn or undersized sheets are a common deferred cost. Beyond that, judge power, canvas, and navigation upgrades by what the individual listing shows rather than assuming a standard package.
What to Inspect
The inspection should center on normal age-related items for a solid fiberglass hull with teak interior. Verify the fin keel and spade rudder attachment and the teak joinery for rot or distortion, and confirm the masthead rig's standing and running rigging match the guiding dimensions above. The modest draft—about 4 feet 10 inches, a little more loaded—should let you haul or survey without heavy travel lift requirements.
Availability and Buyer's Takeaway
Seek listings broadly rather than expecting a local cluster. For the shopper, the takeaway is simple:
- Confirm six-berth layout with convertible dinette and tier quarterberths intact
- Check teak interior for rot; solid fiberglass hull and deck need only normal survey
- Renew masthead running rigging to 31 ft sheets / 77.5 ft mainsheet if original
- Treat her as an economical all-rounder cruiser, not a performance boat
Price & volume trends
Monthly asking-price and listing-volume trends for the Dolphin 31. The line shows the median ask each month; the bars show how many listings appeared.
Monthly breakdown · 5 rows
| Month | Listings | Median ask | Δ vs. last mo. |
|---|---|---|---|
| Sep 25 | 2 | $9,514 | — |
| Oct 25 | 1 | $16,316 | +71.5% |
| Jan 26 | 1 | $20,395 | +25.0% |
| Mar 26 | 1 | $37,248 | +82.6% |
| Apr 26 | 1 | $8,151 | -78.1% |
Where they're listed
Dolphin 31 listings appear across 2 countries. United Kingdom has the most listings with 5 (83.3%), followed by Switzerland.
Country view
6 listings · 2 countries| Country | Median ask | Listings · 12 mo | Active · 90 d | Share |
|---|---|---|---|---|
| United Kingdom | $10,877 | 5 | 0 | 83.3% |
| Switzerland | $37,248 | 1 | 0 | 16.7% |
Comparable models
Similar length, displacement, and era. Open a row to compare that model's market page.
Similar boats to compare
2 similar designs| Model | LOA | Median ask | Listings · 12 mo | Active · 90 d |
|---|---|---|---|---|
| Rustler 31 | 31.42' | $ 17,676 | 14 | 0 |
| Dolphin 31You are here | — | $ 13,597 | 6 | 0 |