Kilz vs Zinsser Primer (What’s The Difference?)

When it comes to choosing a primer, there are two popular brands: Zinsser and Kilz primer. So, what’s the difference between these two basecoats?

Zinsser paint primer is ideal for a variety of painting tasks because it is strong and thick. On the other hand, Kilz primer isn’t thick, it is thin which makes it easier to stir and apply.

Since Zinsser is thick, it means it has better coverage and prevents bleed-through better.

Zinsser Primer

What is Zinsser Primer?

Zinsser is a white-colored paint primer. It is made from different ingredients and there are even different types of it. The primer comes in water-based, oil-based, and shellac-based types.

They have a thick consistency and flow which gives them improved coverage, in most cases, 1 coat of it is enough for proper coverage. Zinsser primer is also universal meaning that all types of paints, oil or water-based can stick over it.

You can use Zinsser primer:

  1. For Covering and Controlling Mold Growth – Zinsser primer is formulated with fungicides to help curb the growth of mold on wood and other porous surfaces. However, not all types have mold control.
  2. For Sealing Pores – Due to its thick consistency and flow helps to seal pores and hairline cracks in the wood.
  3. For Preventing Bleed Through – It also helps to stop bleeding through. If used on a stained surface, it will prevent the stains and oils on the surface from showing through the top coat. Zinsser shellac primer especially is an effective stain blocker known to stop bleeding through and stains.
  4. For Priming New Furniture – Not all primers work well on new furniture. Fresh wooden surfaces are usually riddled with stains, pencil marks, nail holes, and sometimes glue. You’ll need a strong basecoat to seal the holes and cover the furniture — zinsser primer does this perfectly.
  5. For Waterproofing – Zinsser primer is waterproof. This means it’s ideal for kitchen cabinets, countertops, and tables that are more likely to experience moisture.

Kilz Primer

What Is Kilz Primer?

Kilz is a water-based basecoat. Since it’s water-based, its flow is thinner and can be used indoors. You can also spray or apply it with a paintbrush. The primer dries fast since the solvent (water) evaporates faster. 

You can use Kilz primer:

  1. For Changing Colors – Kilz primer is perfect if want to change the color of a finish. It is deep enough to cover deep and light colors to prevent them from showing through the paint.
  2. For Blocking Interior Filth and Stains – It is perfect for blocking indoor and household stains like oil spills, moisture, ink, tannin, pencil marks, and the likes. However, it is not ideal for outdoor stains.
  3. For Penetrating Paints – If you want to use paints that seep into the wood, you should use Kilz primer. The thin nature of the primer means that it allows the paint to bite better in the wood than thicker primers.
  4. For Multiple Coats of Paint – If you are using paints that require many coats, you should use Kilz primer. Since the primer is not thick, it can allow more coats of paint to stick better. You can apply up to 5 coats of water-based paint over it.
  5. For Touch-ups – Kilz primer can help cover corners and small spots. It’s also very easy to work with making it ideal for small-scale tasks, touch-ups, and fixes.

Kilz Primer vs Zinsser Primer

These two primers come with a lot of differences. Here we will compare both based on different features:

The Base

The formula refers to the solvent or thinner in the coating. This is what prevents the primer from solidifying in the can.

Kilz primer is water-based meaning that it uses water as its solvent.

Zinsser primer is oil-based. Its oil-based nature is why its flow is thicker. Most of the characteristics of both basecoats depend on the paint’s base.

The Dry Time

Kilz dries faster than Zinsser primer because it is water-based. For the primer coating to dry, the solvent needs to evaporate.

Since Kilz uses water as the solvent, it will dry enough for paint application within an hour because water evaporates faster. Zinsser primer takes longer to dry because it’s oil-based, and oils take longer to evaporate. 


Zinsser primer is stronger and more durable than Kilz because it is oil-based. Since it is oil-based, it dries slower, meaning the particles have more time to become rigid and compact, making them more durable. 

The Adhesion

Zinsser sticks better to a surface than Kilz primer because it has more adhesive additive in the formula. You can apply it over a surface without sanding. As long as the surface is clean, it will stick.

On the other hand, you’ll need to clean and sand before you can apply Kilz primer. However, both basecoats will not stick to a filthy or greasy surface.


Zinsser has better coverage than Kilz because it is thicker, so you can cover more area with one coat. Since it is thicker, it can cover holes and cracks better. 

On the other hand, Kilz doesn’t fill holes as well because it is thin and doesn’t have good surface coverage. 

Bleed Through

Both primers are great at preventing stains and bleeding through the paint. However, you need more coats of Kilz to prevent bleed-through, Zinsser only needs two coats. 

Mold Resistance

Kilz primer doesn’t prevent or stop mold growth. So, before you apply it over a mold-affected surface, remove the mold and wipe the surface with vinegar. This is to prevent mold growth and allow the basecoat to stick.

The Zinsser mold-remover primer stops mold growth, but other types won’t. However, it’s better to remove the mold manually or at least wipe the surface with vinegar before applying it.

The Cost

You can get a gallon of Kilz primer for as low as $8 while a quart of Zinsser primer will cost the same or more than that. There are four quarts in a gallon. So 1/4 gallon of Zinsser primer might cost you as much or more than a gallon of Kilz.


With Zinsser, you have a broad range of products to pick from. You can pick the oil-based, shellac-based, rust-protection, or even mold-killing primer. You don’t get that many options with Kilz .

Primer Paint Application

Kilz primer is easier to apply and work with because it is water-based and thinner so you can apply more coats and clean up easily. So, it is suited for beginners. 

On the other hand, Zinsser primer is thicker, meaning it’s harder to work with and control. However, you can thin it before applying it. 

Rust Inhibition

Before you paint over a metal surface, you need to apply a primer that has rust inhibition. The rust inhibition protects the metal from corrosion and helps the paint to stick better. Both primers come with rust inhibition in their formula, but the Zinsser has better rust prevention qualities. 


Both primers have almost the same number of products. They come with basic, oil-based, and water-based primers, plus some custom ones such as wood primers. 

Number of Coats

For smooth and clean surfaces, 1 coat of Zinsser primer is enough for good coverage. If the surface has cracks, you’ll need two coats of primer to properly fill and seal the cracks.

On the other hand, you’ll need 2 coats of Kilz primer since it isn’t thick. You can apply up to 3 coats on cracked surfaces.

Final Words

In summary, both primers are great, but they have different features. For instance, Zinsser primer is thicker and has better coverage, while Kilz is thinner and dries faster. 

Tony Adams
Tony Adams

Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about,

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