POR 15 Vs Rustoleum

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To properly rustproof the exterior of a vehicle and keep the paint intact, vehicle owners use POR 15 and Rustoleum. But what’s better?

POR 15 and Rustoleum are two branded rust-prevention coatings. POR 15 is a primer and paint, so it’s more durable and protects against scratches. Rustoleum spray is one coating that can be applied to the car as a second layer or temporary protection.

The objective was to find our vehicle's number one rust prevention tool because of some problems I recently experienced with my classic car. We determined the results and ran a test to compare POR 15 and Rustoleum. Keep reading to find out which brand wins this highly heated contest.

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POR 15 Vs. Rustoleum: Comparison Guide

Anybody who has ever had to deal with rust on their car, truck, or other metal surfaces understands that finding the right product for the job is critical. Two of the most popular solutions out there are POR 15 and Rustoleum.

I recently had the chance to compare the performance of these two products and how well they work to prevent rust. I tested each product on a vehicle in a controlled environment to compare the results accurately.

After these tests, we noticed some interesting differences between the two products. Keep reading to learn more about POR 15, Rustoleum, and the results.

What Is POR 15?

POR 15
POR 15

Any car enthusiast has likely heard of POR 15, a rust-preventive paint that's designed to help protect vehicles from the elements. But what exactly is it, and how does it work?

POR 15 stands for "Paint Over Rust," an industrial-strength coating with advanced resins and solvents. It's formulated to stop existing rust and guard against future corrosion.

This robust paint bonds itself firmly onto metal surfaces. The chemical bond to rusted metal helps create an effective barrier between our vehicle’s vulnerable surfaces and corrosive elements like road salt or moisture in the air.

After using it, the coating will become rock-hard and non-porous. Its chemical composition allows it to remain flexible despite extreme heat or cold temperatures.

How Do You Use POR 15

As we’ve mentioned, POR 15 is unlike other rust prevention methods. It requires three steps to be successful. Follow them below.

Step One: Clean The Surface Area

To use POR 15, we must first prepare the area for application. This includes removing loose rust or flaking paint and cleaning off dirt or grease. Proper prep is critical.

Typically, any POR 15 purchase will also include a cleaner. The degreaser option works best because it can remove everything in one application and never leaves residue, fumes, or flammable solvents.

Step Two: Prep The Area With Primer

Next, we can move on to the primer step. The kit will include a metal prep coating to create adhesion on the top of the surface before step three.

Step Three: Apply The POR 15 Coating

Finally, we can apply the actual coating itself. The three steps can be excessive for some people, so POR 15 is less commonly used. We also recommend mixing it with a lacquer thinner, especially for white paint.

But it provides plenty of benefits and ranks as one of the best rust-prevention methods for car and truck owners.

What Is Rustoleum?


If you’ve ever been around DIY projects or taken on a home improvement project, chances are you have heard of Rustoleum. It's one of the most popular brands for protecting metal surfaces from rust, corrosion, and other damage.

Rustoleum is a paint product that can be used as a primer and final coat to protect metal surfaces fully. Expect excellent UV protection too.

It also improves the longevity of cars suffering from metal deterioration. This makes it perfect for outdoor furniture, handrails, and any other metal surface exposed to the elements.

It’s also become popular for car use because it’s fast and durable. It won’t provide as much protection as POR 15 but can work in unique situations.

How Do You Use Rustoleum?

When applying Rustoleum products, removing all dirt or debris from the surface before using it is crucial to ensure proper adhesion. Priming is not required, but it can help with adhesion on some surfaces.

After cleaning off any residue left behind, an applicator wire brush can apply a thin layer evenly across the entire area. Because it’s oil-based, this is not required, and it can dry independently without a brush.

Depending on how heavily oxidized the surface is will determine how many coats need to be applied before full coverage takes effect. A coat will take 1-2 hours to dry, and we recommend 2-4 coats for vehicles.

POR 15 Vs. Rustoleum: How Are They Similar?

Wondering what to do with all the rust on the outside of a vehicle can be stressful. I’ve felt it before, but both of these products can be a lifesaver. Let’s review the similarities to understand better how they work.

Anti-Rust Protection

POR 15 and Rustoleum are rust-preventive coatings designed to protect metal surfaces from corrosion. Both products come in various colors and finishes, allowing for customizability regardless of the application method.

No Sanding Requirements

Another great thing about both of these products is that no sanding is required before applying them on the surface of a car. Both can be sprayed or painted directly over the top of the rust to improve the surface quality and remove that rusty look.

Both Can Be Painted Over

Lastly, these are two paint-ready formulas. Despite their key differences, it’s possible to paint right on top of POR 15 and Rustoleum. This is typically how people restore vehicles.

POR 15 Vs. Rustoleum: How Are They Different?

Application Method

The most significant difference between POR 15 and Rustoleum is the application method. POR 15 is a three-step process that applies like a paint coating. Clean the surface, use primer on the surface, and finally, apply the rubberized paint POR 15.

Rustoleum is much easier to use and only requires one step and takes  just a couple minutes. It comes in a spray can, and the oil-based coating applies directly to the surface; no metal prep work is needed.

This is one reason the beginner typically opts for Rustoleum over POR 15, especially when using proper urethane paint.

Seal & Cover

POR 15 is a three-step application process with a crucial cleaning step for better adhesion capabilities. It’s a rubberized paint and uses an extra layer of primer to create a better cover and seal.

Oil-based paint Rustoleum has no cleaning or priming requirements. Instead, we can spray one coat on our car and expect results without any preparation. It’s better to clean the car first and use multiple coats, but it’s not always necessary.


When it comes to cost, Rustoleum is usually the cheaper option. It has a much lower price point than POR 15, partly because of Rustoleum’s easy one-step spray application process and fewer steps involved in preparation.

POR 15 offers more layers and more robust protection against moisture penetration. However, this extra layer of security also means that it carries a higher price tag than its counterpart.

Durability & Strength

When comparing the durability and strength of these two products, POR 15 takes the lead. I saw much longer rust prevention on my vehicles after using POR 15.

Both of these products should be viewed differently. POR 15 is ideal for restoring vehicles with a more extensive surface area. It’s meant for larger, more complex restoration jobs, while Rustoleum is a fast and easy prevention method.

Are There Any Other Alternatives To POR 15 & Rustoleum?

If you’re like me, you’ve been trying to find a reliable solution for rust prevention and protection that doesn’t come at an exorbitant price.

POR 15 and Rustoleum are two of the leading products on the market, but they are not for everybody. Looking for alternatives, I stumbled upon some great options that also work.

Epoxy Primer

Epoxy primer is a cheaper alternative to POR 15. It can be sprayed directly over rusty surfaces as a primary chassis coat, although we prefer to remove as much rust as possible before applying it to the vehicle's exterior.

The primer will cover the rust and create a smooth and clean surface for paint later. It’s more of a quick and cheap fix than a long-term solution like POR 15.

Powder Coating

Powder coating is a much more advanced process than POR 15 or Rustoleum. This is professionally done, and the surface must be prepped and cleaned beforehand.

Proper powder coating also requires time to bake in the oven. While it takes more time and costs more, the finish is unmatched and lasts much longer too.

Rust Bullet

Rust Bullet works similarly to POR 15 but needs less prep work, like Rustoleum. It’s like combining the best of both worlds to get a fast application with added durability and surface protection.