O'Neill Heat Wetsuit Review

O'Neill Heat Wetsuit Review

The Heat is one of O’Neill’s longest-running wetsuits and has built a cult following over the years. Known for its simple, rugged design, the Heat is lighter and more flexible than ever before. We get quite a few questions about this suit, so we’ve decided to take a closer look at the unique O’Neill Heat wetsuit with a full review.

First introduced back in the ’80s, the Heat has been going strong as one of O’Neill’s classic models and remained ever-popular with older surfers and surfers who prefer back zips. Available as a 3/2mm and 4/3mm, the Heat’s design for years has stayed mostly the same, with minor tweaks every so often. However, back in 2020, the Heat was given a full overhaul with a lot of improvements.

“The Heat back zip wetsuit is unbeatable value for serious surfers. Out of all the high-end options, it's our top pick due to its more affordable price tag compared with other suits at $100+.”

Highlights and Features

  • Insanely flexible Technobutter 3 neoprene
  • Warm Firewall liner
  • Durable, water-resistant zipper
  • Front and back smooth skin panels

O’Neill Heat

Back Zip entry on the O'Neill Heat Wetsuit

Neoprene and Liners

The Heat is entirely made of O’Neill’s top TechnoButter 3 Neoprene (TB3). This is the same stuff you’ll find on their Hyperfreak, and it’s just about the most flexible rubber on the market. Aside from its stretch properties, TB3 is also very lightweight and wears comfortably on your skin. If you have ever owned a Heat in the past, putting this version on will be night-and-day different in terms of weight and flexibility.

Another feature taken from O’Neill’s top shelf is an internal linear that they call TechnoButter Firewall. If you flip the Heat inside-out, this is the red material that runs through ¾ of the suit from the chest down. This is the same internal linear found on some of O’Neill’s most expensive suits, like the Psycho Tech. Basically, this liner is incredibly comfortable, better retains heat in the core and legs of your body, and dries quickly once out of the water.

The arms and shoulders don’t have this liner in them, but that’s only to keep them free and as unrestricted as possible.

Interior Firewall Lining and Taped seam construction on the O'Neill Heat Wetsuit.

Seams and Stitching

As far as seams go, the Heat has the best of the best. Without a doubt, the exterior fluid seam weld does an excellent job of sealing off seams from the cold ocean water. In addition, O’Neill uses durable chemical-free glue to bind the neoprene panels together.

Fit and Cut

We found this suit to be very comfortable. With a smooth back zip entry, it was easy to get in and out of and, once on, fit well. These suits run true to size; if anything, they allow for a few extra pounds if you’re just outside the recommended weight. Like all O’Neill suits, the Heat fits surfers with wide shoulders or a big chest especially well.

Back Zip Entry on the O'Neill Heat Wetsuit.

Entry and Zipper

The O’Neill Heat definitely has a strong following to it, partially because of its accessible entry system. Nowadays, it’s challenging to find a high-performance wetsuit offered in a back zip option. So for surfers who love back zips wetsuits, the vast majority of their choices are entry to mid-level suits.

The back zip entry on this wetsuit is super smooth, using the best zipper in the industry, the O’Neill Red Zone Zipper. The Red Zone Zipper is aptly coated in a red urethane material and is the most watertight and durable zipper that we know of. These zippers thread smooth and feel like they came off a piece of commercial fishing gear as opposed to the cheap, thin-style zippers found on other suits.

Interior Lining on the O'Neill Heat Back Zip Wetsuit.


Cold water surfing can be challenging unless you have the right gear. If you live in an area where a wetsuit is required, you understand how lightweight and flexible neoprene is priceless. The Heat certainly delivers in both categories. Cut down on paddling fatigue while extending your sessions with that second-skin feeling of Technobutter.

Furthermore, the Firewall liner and fluid seam weld provide optimal warmth when the water temperature drops. Another great warmth feature is the front and back smooth skin paneling. It does an incredible job of cutting down on wind chill while also absorbing sunlight.

Interior knee pads on the O'Neill Heat Wetsuit.

Value and Durability

Along with the O’Neill Mutant, the Heat is one of those suits that we never seem to have problems with and rarely see come back to the shop for warranty repairs. It helps that it’s a simple design, which doesn’t really leave a lot to go wrong, especially when it features top-quality materials.

O'Neill Heat 4/3 Back Zip Wetsuit.

Customer Feedback

“I've been wearing O'Neill Heat suits for over 20 years and would not consider any other suit. They fit great and last if you take care of them. The new Technobutter material allows for greater movement for paddling.”

- Ed

I’m 6’6,” and 205 lbs, and finding a good wetsuit is way easier than finding a perfect wife/husband/partner. The O’Neill Heat XLT is great. The size fits as perfectly as it could for someone as “circus freakish” as I am, and the comfort of the inner lining is fantastic. So far, the water temps are cool but not cold, so the review is based on comfort and fit alone. 10 out of 10!”

- Tall Guy Review

This is my second O'Neill wetsuit. The first was exactly what I needed for SoCal winter. The Techno Butter is especially stretchy without giving up warmth. I know this one will be just as good as we head into late fall and winter conditions.”

- Daphne

Other O’Neill Back Zip Wetsuit Reviews

  • O’Neill Psycho Tech Wetsuit Review
  • O’Neill Hyperfreak Fire Wetsuit Review
  • O’Neill Epic Wetsuit Review

Final Thoughts

The Heat back zip wetsuit is unbeatable value for serious surfers. Out of all the high-end options, it's our top pick due to its more affordable price tag compared with other suits at $100+. Plus, you get uncompromising performance and quality that truly stands out.

Interested in one of thee most high-performance back zips on the market? Take a look at the newly updated Psycho Tech. If you are a fan of O’Neill suits, but the Heat is outside of your budget, we recommend the tried and true Epic line.

Hopefully, this review helped answer some questions you may have had about the Heat. If there's anything we didn't cover or if you have any other wetsuit questions in general, feel free to leave a comment below, send an email to support@cleanlinesurf.com, or call us toll-free at 1-888-546-6176.