Measure the size of the pool. Make certain to include the top rails in your measurements. Some pools have wider top rails that need to be taken into account. Record your measurements in a note pad.
Take into consideration how low you will drop the water level. Most pool covers will come with enough material to compensate for a water level that is reduced up to 12". If you need to drain the water level more than that, you will need to purchase a larger cover.
Once you have selected the style of winter cover (solid or mesh, you will want to review the cover size. Two sizes will usually be displayed on the item page, the pool size and cover size. For example, if you have a 12' round pool, the cover size will be 16' round.
Once you have received your new winter cover, carefully remove it from the box and measure it to ensure it is the correct size. If it is incorrect, please contact the dealer you purchased the cover for further instruction.