A properly fitted boat cover protects your vessel from sunlight, rain, dirt, leaves, bird droppings, and other outdoor contaminants. The right cover can also reduce cleaning time and help preserve your boat’s upholstery and finish. Before selecting a cover, however, you need accurate measurements of your boat’s centerline length and beam width.
This guide explains how to measure your boat for a cover, which accessories to include, and how to use your measurements to find the best available fit.
What You Need to Measure Your Boat
Only a few basic items are needed:
- A flexible, non-stretching tape measure long enough for your boat
- Paper or a phone for recording measurements
- A second person to help hold the tape measure
- A ladder or step stool if needed to reach elevated areas safely
If you need measuring equipment or other supplies for the job, browse our selection of boat hardware and tools.
Measure your actual boat instead of relying exclusively on its model name or advertised length. Manufacturer dimensions may exclude certain platforms, brackets, rails, or other features that can affect cover fit.
Boat Measurements You Will Need
| Measurement | Where to Measure | Important Reminder |
|---|---|---|
| Centerline length | From the farthest point of the bow to the farthest point of the stern included beneath the cover | Measure in a straight, level line rather than following the boat’s contours |
| Beam width | Across the widest part of the boat | Measure from the outermost point on one side to the outermost point on the other |
| Height and accessory clearance | Around consoles, windshields, rails, towers, and other permanent equipment | Confirm that the selected cover is designed to accommodate these features |
How to Measure Your Boat for a Cover
1. Identify Your Boat Type
Begin by determining your boat’s general style. Center-console boats, bass boats, bowriders, pontoons, deck boats, fishing boats, and cuddy cabins have different profiles and require differently shaped covers.
Two boats with the same centerline length and beam may still need different covers if their consoles, windshields, railings, or seating arrangements are different. Select a cover made for your boat style rather than relying on dimensions alone.
2. Prepare the Boat
Place the boat on a level surface when possible. Remove portable items that will not remain under the cover, including detachable fishing seats, coolers, watersports equipment, and loose accessories.
Leave permanent or regularly installed features in place. These may include:
- Windshields and consoles
- Bow and side rails
- Fixed fishing chairs
- Trolling motors
- Permanent swim platforms
- Antennas or lights that cannot be folded or removed
Fold down or remove accessories only if they will normally be stored that way while the boat is covered.
3. Measure the Centerline Length
Measure in a straight line from the farthest point at the bow to the farthest point at the stern that the cover must protect. Keep the tape measure level and parallel to the ground.
Do not run the tape over the windshield, seats, console, or other raised components. Following the boat’s contours will produce a measurement that is longer than its actual centerline.
Whether a swim platform, bow pulpit, motor bracket, or similar feature should be included depends on the selected cover. If the feature is permanently attached and must remain beneath the cover, include it when comparing your measurements with the cover manufacturer’s sizing instructions.
Most standard boat-cover measurements do not include the outboard motor itself. Outboards are commonly protected with a separate motor cover, but you should always check the specific product description before ordering.
4. Measure the Beam Width
The beam is the widest point of the boat. Stretch the tape measure in a straight line from the outermost point on one side to the outermost point on the opposite side.
Keep the tape level, and do not wrap it over seats, consoles, or railings. If you are unsure where the boat is widest, take measurements at several locations and record the largest result.
5. Record Permanent Accessories
Make a list of anything that could affect the cover’s fit. A cover designed for a low-profile bass boat, for example, may not accommodate a tall windshield or center console even when its listed length and beam appear correct.
Important features to note include:
- Center or dual consoles
- T-tops and hardtops
- Wakeboard or ski towers
- Bow pulpits
- Jack plates and motor brackets
- Swim platforms
- High bow rails
- Permanent trolling motors
Boats with towers, hardtops, or unusually tall equipment may require a specialty cover or a custom-made solution.
6. Double-Check Your Measurements
Measure the centerline and beam a second time before ordering. Record measurements in feet and inches, and do not round down. A cover that is too small may be difficult to install, place excessive stress on seams, and leave portions of the boat exposed.
How to Use the Wholesale Marine Boat Cover Guide
Once you have recorded your measurements, visit Wholesale Marine’s selection of boat covers. When available, search by the boat’s manufacturer, model, and year to find compatible options.
If your manufacturer or model is not listed, shop by boat style and compare your centerline length and beam with the dimensions shown for each cover. Also verify that the cover accommodates your boat’s drive type, consoles, windshield, rails, and permanent accessories.
When comparing covers, consider more than size. Fabric weight, UV resistance, water repellency, breathability, warranty coverage, tie-down design, and suitability for storage or trailering can all affect performance.
Should You Choose a Custom-Fit or Universal Boat Cover?
Custom-Fit Covers
A custom-fit cover is patterned for a specific boat manufacturer, model, and year. It generally follows the boat’s contours more closely and may include allowances for standard consoles, windshields, and other factory-installed equipment.
A custom-fit cover is often the best choice when:
- Your exact boat is available in the cover guide
- You want a closer, more tailored fit
- The boat has a distinctive layout or profile
- You need a cover designed around standard factory equipment
Universal or Semi-Custom Covers
Universal and semi-custom covers are designed to fit a range of boats with similar dimensions and hull styles. They can offer a practical and economical solution when an exact model-specific cover is unavailable.
For the best fit, match both the boat style and dimensions. Do not select a cover based solely on the advertised boat length.
Common Boat-Measuring Mistakes
- Measuring over the windshield, seats, or console
- Following the curve of the hull instead of measuring in a straight line
- Using the boat’s advertised model length without measuring the actual vessel
- Forgetting to account for a permanent swim platform or bow pulpit
- Including the outboard when the cover is not designed to cover it
- Ignoring tall rails, towers, consoles, or fixed accessories
- Measuring the beam at a convenient point instead of the widest point
- Rounding measurements down to fit a smaller cover
- Ordering by dimensions without confirming the correct boat style
Check the Fit Before Using the Cover
When the cover arrives, carefully unpack it and place it over a clean boat. Confirm the fit before exposing the cover to dirt, rain, or extended outdoor use in case an exchange is necessary.
The cover should reach below the rub rail where intended and fit securely without placing excessive tension on seams or corners. Pad windshields, cleats, and other sharp or projecting objects to reduce wear.
Use every provided tie-down point and follow the cover manufacturer’s installation instructions. Replacement straps and related boat-cover snaps and fasteners are available when additional securing hardware is needed.
For outdoor storage, support the cover so rainwater cannot collect in low areas. Standing water adds considerable weight and can stretch the fabric, damage support poles, and place unnecessary stress on the boat and cover.
Frequently Asked Questions
How do I measure the length of my boat for a cover?
Measure the boat’s centerline in a straight, level line from the farthest point of the bow to the farthest point at the stern that will be covered. Do not measure up and over the windshield, seats, or other raised components.
What is the beam measurement on a boat?
The beam is the boat’s width at its widest point. Measure straight across from the outermost point on one side to the outermost point on the other while keeping the tape level.
Should I include the outboard motor in the boat’s length?
Usually, the outboard motor is not included in the boat’s centerline measurement because it is protected separately. However, sizing methods vary, so confirm the instructions for the specific cover you are considering.
Do I include a swim platform when measuring for a boat cover?
Include a permanently attached swim platform if it must fit beneath the cover and the cover manufacturer instructs you to include it. Some model-specific covers account for factory platforms separately, so check the product’s sizing information.
Should I order a larger cover if my measurement falls between two sizes?
Do not round your measurement down. Select a cover whose stated size range accommodates the boat’s full centerline and beam, while also matching its style and profile. Avoid adding unnecessary extra length because an excessively loose cover can flap and collect water.
Can I use my boat’s model number to determine its cover size?
A model number or advertised length is a useful starting point, but it may not represent the boat’s exact dimensions. Measure the actual boat and compare those measurements with the cover manufacturer’s fit information before ordering.
Can a standard boat cover fit over a T-top or wakeboard tower?
Most standard covers are not designed to fit over tall T-tops, hardtops, or wakeboard towers unless the product description specifically says otherwise. Boats with these features may require a specialty or custom-fit cover.
Find the Right Cover for Your Boat
Accurate centerline and beam measurements make it easier to find a cover that protects your boat without excessive tension or loose fabric. Measure the actual vessel, account for permanent accessories, confirm the correct boat style, and compare all of that information with the cover manufacturer’s fit guidelines.
Wholesale Marine carries boat covers for numerous boat styles, manufacturers, and models. If you are uncertain about fit, have your boat’s manufacturer, model, year, centerline length, beam width, and accessory information available when requesting assistance.