16 Mil vs 12 Mil Solar Pool Covers | Picking The Right Thickness

16 mil solar pool covers retain more heat and resist punctures better than 12 mil, but 12 mil wins for lighter weight and lower cost.

Choosing between a 16 mil vs 12 mil solar pool cover comes down to one trade: maximum heat retention and durability versus easier handling and a smaller dent in your wallet. Thickness is measured in mils—a 12 mil cover is 0.012 inch thick, while a 16 mil cover is 0.016 inch thick. The thicker material offers better insulation and toughness, but it’s noticeably heavier, bulkier, and harder to manage on a daily basis.

For most residential pools, 12 mil is the sweet spot. For pools in cooler climates, windy spots, or where you want the warmest possible overnight water, 16 mil is the heavy-duty choice worth its extra weight.

Why Cover Thickness Actually Matters

Mil is the standard thickness unit for pool covers. The higher the number, the thicker the material—and the thicker the cover, the better it traps heat and withstands sun, chemicals, and punctures.

The trade-off is physical. Thicker covers weigh more, fold into bulkier piles, and put real strain on your arms—and your reel. Leslie’s buyer guide breaks down the typical temperature gains and warranties by thickness:

Those figures show why 16 mil earns its premium reputation. But a warranty only helps if you actually use the cover—and a blanket that’s a pain to roll up tends to stay off the pool.

12 Mil: The Balanced Choice For Most Pools

The 12 mil cover is the standard recommendation for a typical residential pool.

You get meaningful heat retention without the wrestling match. A 12 mil blanket is light enough for most people to handle by hand or with a basic reel, and it’s easier to fold, store, and trim. If your pool gets decent sun and you don’t need maximum overnight warmth, this is the practical, budget-friendly pick.

Here’s where 12 mil fits best:

• Mild to warm climates with shorter heating needs
• Pools you heat only for weekend use, not daily swimming
• No power reel installed, and you’ll be rolling it manually
• Budget-conscious buyers who want solid performance per dollar

16 Mil: Maximum Warmth And Durability

When you want the warmest possible water and a cover that lasts, 16 mil delivers.

That extra thickness also means extra weight. That’s a manageable number on a good reel but a genuine struggle to lift and fold by hand every day. Some reels, especially low-profile models, may bend or rub under the bulk of thicker blankets, per In The Swim’s guidance.

16 mil is the right call when:

• Your pool sits in a cooler climate or exposed, windy area
• Overnight heat retention is a top priority for daily swimming
• You want maximum puncture and UV resistance for a longer service life
• A reel system is already installed or you’re willing to buy one

If you’re leaning toward the heavy-duty option, our tested picks for the best 16 mil solar pool cover compare the top models side by side.

Color Choice: Clear vs Blue

Thickness isn’t the only decision. Color affects performance too. A clear cover lets the most sunlight through, maximizing solar gain—ideal if warmth is your single goal. A blue cover trades a little heat gain for a nicer appearance and some reduction in algae-friendly light penetration. For most buyers, blue offers the best compromise.

FAQs