Grady White Marlin 300

by admin
Grady-White Marlin 300

The Grady-White Marlin 300 is a fully-equipped blue-water fishing vessel and she can accommodate up to four people for overnight excursions. The walk-around design adds safety for fishing far offshore in sloppy conditions, while the aft cockpit has plenty of space for trolling as well as for after-hours entertaining.             

The Marlin 300’s SeaV2 hull and overall design make it an offshore saltwater fishing vessel first and foremost. The 9.30m LOA and cabin below deck are a marriage of practicality and convenience. Perhaps the most important thing about the Marlin 300 is that it is a lot more comfortable — dryer and safer — for extended trips far offshore for bluewater fishing. Because she is not an open boat, when the sea gets rough and confused, her closed foredeck and protected bridge and cockpit make her a welcome alternative to any centre console on the market.

The addition of Strataglass between the windshield and the hardtop allows the bridge to be buttoned up for a cozy ride home when weather turns foul. In addition, the square footage in her cockpit is greater than what is found in most centre consoles her size between the lead post or bait-prep station and the transom.

The added advantage of the design is that she has an enclosed head with sink and shower, a full galley, and a U-shaped seating area with a convertible table for dining which can be made into a double berth. Another berth is amidships. For this reason, the Marlin 300 can also be used for cruising and even short weekend overnighting.

The Marlin 300 is the largest boat in Grady-White’s “Walk Around” series, but frankly, we think of her more as more of an express fish boat. “Walk Around” refers to the side decks which are recessed to provide secure footing when working a fish around the boat. We think these side decks are an excellent compromise between an express and a centre console. For all of these reasons we find that she provides a lot more utility than the ubiquitous centre console.

A special feature of the Marlin 300 is the SeaV2 Hull Design. The hull was designed by C. Raymond Hunt and Associates which knows as much about designing a deep-V hull as any firm on the planet. Her high deadrise forward which warps to a moderate deep-V aft to combine stability with riding comfort.

The stern of the Marlin 300 is nearly all engine with a stainless steel re-boarding ladder on the starboard side. The ladder is moulded-into the fiberglass platform, and just below it begins the 300’s rub rail, which circles the entire boat and is made of high-quality PVC with a stainless steel insert.

Just forward of the re-boarding ladder is the transom door. The stout door is made of fibreglass with a heavy-duty stainless steel latch on the inside just below the cockpit bolster that extends to include the transom door. The door opens out, which we prefer so it does not restrict cockpit space and can be used in emergency dewatering.

Fishing Space

The cockpit on the Marlin 300 is the primary fishing space, and is broken up forward by two steps up to the helm deck and access to the cabin below. A bolster wraps around the cockpit with four dedicated rod holders mounted into the reinforced gunwales. Rod racks are under both gunwales. Just below these are toe rails that can be used when hauling in the big one. On the hardtop legs, two to each side, are stainless steel rocket launchers.

Along the transom is the freshwater cockpit shower. The majority of the transom panel, however, is taken up by the 300’s 274 L fishbox, which has LED lights and drains overboard.

On the port end of the transom is a lift-out storage bin under a fixed cutting board. Under the bin is access to two battery banks with four batteries.

There is a fold-down bench seat facing forward on the transom as well with marine-grade weather-resistant upholstery. Below the seat is an access hatch to levered seacocks and the 5 kW generator.

The levered seacocks are a very good idea and something that we only rarely see. They enable the seacock to be turned off quickly in an emergency without having to fish around for a long reach to the thru-hull. More builders should use this concept when not able to put the seacock within easy reach.

Forward the rod holders in the gunwales are fiberglass steps up to the side decks on each side. Adjacent to the steps up to the helm on the centreline on each side are two stations: to port is a 121 L insulated raw water live well with a light, full column distribution inlet, and overboard drain; to starboard is a rigging station with a freshwater sink, insulated bait box, and lockable drawers. For both, cushions can be easily installed just on top, creating additional cockpit seating space.

Two fiberglass steps up in the centre of the boat from the cockpit to the helm. The bottom step lift up to reveal storage space below.

The Marlin 300 comes standard with two Deluxe II helm seats, which are both horizontally and vertically adjustable, with armrests that can flip-up and out of the way. Both helm seats have lockable storage spaces in their bases. The boat we tested had optional Command Elite seats that are horizontally and vertically adjustable with deluxe cushioning for smoother ride. Flip up bolsters, too. We recommend this option.

Grady-White also offers the option to eliminate the companion bridge seat and replace it on the port side with a lounge seat that has a backrest that faces forward but also wraps along the portside gunwale for versatility in a social setting.

The hardtop comes standard on the Marlin 300 and comes as a painted aluminium frame, with radio box, storage nets, spreader lights, four side mounted rod holders, outrigger plates, and drop, front and side curtains.

The helm station has a stainless steel steering wheel with throttle just to starboard on the forward flat panel. A compass divides the dash’s flat panel. Rocker switches and the standard trim tab controls are to the right. Grady-White offers the Yamaha Helm Master as an option on the Marlin 300.

One of Grady-White’s big innovations is their Captain Grady system, which works on either an iPad or iPhone or other smart devices as an app and provide operations guides, FAQs, and troubleshooting. Forward, the windshields are ventilated tempered glass, with windshield washers and two standard windshield wipers.


Access to the cabin comes via three fiberglass stairs to port of the helm station. The decks on the 300’s lower deck are teak and holly (standard), and immediately to port upon entry is the boat’s galley. It has a microwave, glass electric top stove, refrigerator, Corian countertop, stainless steel sink, and trash drawer. Above is storage behind sliding cabinet doors.

Immediately to starboard off the access stairs, through a duck-down entrance, is the aft double berth, which has netted storage on the far wall, as well as rod storage overhead.

Opposite the galley on the starboard side is the 300’s enclosed head. It has a sink, shower, and lamp, with a VacuFlush marine head that has a 38 L holding tank and pump-out.

Forward below deck is a dining space that can convert to a V-berth. The “C” shaped seating section wraps around a cherry wood table and has a backrest wrapping around the entire space. The table can be adjusted down to be level with the seating, allowing the addition of a filler cushion for conversion to a berth.

Removal of the cushions in the seating section itself reveals storage cubbies below.

Overhead are two reading lights, as well as three rod storage racks to each side, which flank the opening overhead latch that has both a screen and a shade depending on desired level of natural light and fresh air.

Walkaround to Bow

The Marlin 300 is a walkaround cuddy cabin, and from an easy step-up in the cockpit you’re up onto the side-decks, with the 316 grade stainless steel guide rails extending all the way up to the foredeck. On the bow, just forward the windshield, is the opening Bowmar hatch above the lower deck V-berth. This surface can also be covered with the optional cushions and converted into a seating space.

Forward the seating space is the anchor windlass, which has foot controls to port (as well as controls at the helm), and a bow pulpit that includes a roller. To the starboard side of the windlass is the anchor locker, under a hatch with a stainless steel latch.

Power Options

The Marlin 300 offers three choices for power; Yamaha Twin 250-hp or a single 300hp or 350hp. With a pair of Yamaha V6 4.2L 300-hp engines powering our test boat, we had an estimated test weight of 4,815kg. Our top speed at wide open throttle was 43.4 knots.

Best cruise came at 3500 rpm where we recorded 24.0 knots, burning 68 lph, getting 1.3 4.9 LPNM for a range of 338 miles with a 10% fuel reserve. She was fast on plane — 3.0 seconds, hitting 20 mph in 3.9 seconds and 30 mph in 6.9 seconds.


The Grady-White Marlin 300 has passed the test of time. The builder first introduced this series over 30 years ago and they are still in the line up — but changed and updated over the years. That is saying something as most boat models last from three to seven years before they are discontinued. At 9.14 m this vessel is big enough, and seaworthy enough to take offshore into the blue. The Grady-White Marlin 300 is a top-flight fishing boat, with plenty of amenities aimed at such an excursion.


  • Model & Model: Grady White Marlin 300                    
  • Price as tested: $NZ
  • Priced from: $NZ
  • Type: Cabin                        
  • Construction: GRP
  • LOA: 9.30m   
  • Beam: 3.23m
  • Deadrise: 19.5 deg   
  • Test Power: 2 x Yamaha 300
  • Propellers: 15 1/2″ x 17 SWS II SDS
  • Power options: Outboard     
  • HP Range: 300hp-500hp       
  • Fuel Capacity: 1067 litres 
  • Manufacturer: Grady White


Grady White Marlin 300

Fuel capacity:








Range  (NM)

























































related articles