Home/ Boats/ Marine Projects Ltd. (Uk)/ Sigma 33 C
Sailboat Specifications

Sigma 33 C

Masthead Sloop · Fin W/Spade Rudder

Designed by David Thomas · Built by Marine Projects Ltd. (Uk) · First built 1979

+ Add to Compare
LOA 32.50 ft  ·  Beam 10.50 ft  ·  Displacement 9,500.00 lb  ·  Sail Area 497.00 ft²  ·  Masthead Sloop  ·  Fin W/Spade Rudder
About the Sigma 33 C Sailboat

Built by Marine Projects Ltd. in the UK starting in 1979, the Sigma 33 C represents David Thomas's approach to creating a versatile coastal cruiser with respectable performance characteristics. This 32.5-foot masthead sloop strikes a practical balance between comfort and sailing ability, making it well-suited for weekend coastal adventures and extended cruising in protected waters. The design features a modern fin keel with spade rudder configuration that provides good maneuverability and responsive handling. With a displacement of 9,500 pounds and 497 square feet of sail area, the boat offers moderate performance without sacrificing stability. The comfort ratio of 22.78 suggests a motion that's acceptably gentle for cruising, while the capsize screening value of 1.99 indicates reasonable stability for coastal conditions. Thomas designed the Sigma 33 C with practicality in mind, creating generous interior volume within the 10.5-foot beam. The fiberglass construction ensures durability and relatively low maintenance, important considerations for cruising sailors. While not a speed demon, this yacht delivers reliable passage-making capability with a theoretical hull speed approaching 7 knots, supported by an 18-horsepower auxiliary engine for calm conditions or tight marina work.

Market Price Estimate Beta
Small sample size. This estimate is based on fewer than 5 listings and may not be representative of the true market. Use with caution.
$15,000 – $15,000
typical asking price
Median $15,000  ·  1 listing used
All listings
$15,000 – $15,000 1
About this estimate ▾
Dimensions & Specifications
LOA (Length Overall) 32.50 ft / 9.91 m
LWL (Waterline Length) 26.25 ft / 8.00 m
Beam 10.50 ft / 3.20 m
Max Draft 4.83 ft / 1.47 m
Displacement 9,500.00 lb / 4,309 kg
Sail Area (Reported) 497.00 ft² / 46.17 m²
Design & Construction
Hull Type Fin w/spade rudder
Rigging Type Masthead Sloop
Construction FG
Designer David Thomas
Builder Marine Projects Ltd. (UK)
First Built 1979
Owner Reviews

No owner reviews yet — be the first to share your experience with this boat.

Engine & Accommodations
Engine Make Volvo
Engine Model 2002
Engine Type Diesel
Horsepower 18
Fuel Capacity 15 gals / 57 L
Frequently Asked Questions

What is the Sigma 33 C's sail area to displacement ratio?

The Sigma 33 C has a Sail Area to Displacement ratio (SA/D) of 17.79. Values between 14–18 are typical cruising sailboats; 18–22 is cruiser/racer; over 22 is performance racing.

What is the Sigma 33 C's comfort ratio?

The Sigma 33 C has a Ted Brewer Comfort Ratio of 22.78. A ratio over 30 indicates good offshore comfort; over 40 is very comfortable offshore.

Is the Sigma 33 C safe for offshore sailing?

The Sigma 33 C has a Capsize Screening Formula value of 1.99. Values under 2.0 are considered acceptable for offshore sailing; under 1.8 is ideal.

What is the hull speed of the Sigma 33 C?

The theoretical hull speed of the Sigma 33 C is 6.87 kn knots, calculated from its waterline length.

How much does a Sigma 33 C weigh?

The Sigma 33 C has a displacement of 9,500.00 lb and a length overall (LOA) of 32.50 ft.

How much does a used Sigma 33 C cost?

Based on 1 recent market listings, used Sigma 33 C sailboats typically sell for between $15,000 and $15,000, with a median asking price of $15,000. Price varies significantly based on year, condition, location, and included equipment.

Who designed the Sigma 33 C?

The Sigma 33 C was designed by David Thomas, first built in 1979.