Tire Repair Guidelines: When to Patch, Plug or Pitch a Tire

We get it: You want to get as many miles out of your tires as possible. When it comes to fixing flat tires, you'd rather patch or plug it than replace it, especially if you can get a few more miles out of the repaired tire. Understood.

There are ways to fix tires instead of buying brand-new ones. You can use a patch or plug sometimes. We'll explain. In this guide, Tire Agent explains tire patches and tire plugs, when it's safe to use them, and when to avoid them like the plague.

The U.S. Tire Manufacturers Association has established tire repair guidelines, which include the following:

1. A plug by itself is considered to be an unacceptable repair.
2. A patch by itself is not recommended because it doesn't fill the puncture channel.
3. Repairs should be made to the tread area only of a tire (see tire repair zone illustration below).
4. Repairs can be considered on punctures no larger than 1/4 of an inch. 
5. Do not repair damage to the shoulder or side wall of a tire; the tire is considered unsafe and should be replaced.
6. The entire tire must be removed from the assembly and fully inspected to assess damage. 
7. Tire repairs cannot overlap previous tire repairs. A previously repaired tire with new damage is considered to be an unrepairable tire.
8. A plug-patch combo is the best repair.  

Tire Patches vs Tire Plugs: What's the Difference?

What are Tire Patches? Can I Patch My Tire?

Tire patches are repairs that seal punctures in the inner lining of a tire, on the tread surface, which often have been caused by nails, screws and other road debris.  

Can you patch a tire yourself? The process for patching a tire is involved, and unless you have the right equipment, you're better off taking it to a tire professional.

Tire patching is considered a high quality repair that's more involved than tire plugging, which we describe in the next section. The steps to patch a tire:

1. Remove the tire from the rim.
2. Inspect it for damage.
3. Use a die grinder to smooth and buffer the region surrounding the puncture so that there is enough room for the patch to adhere to.
4. Apply vulcanizing cement after buffing, allowing it to dry to a tacky state before applying the patch.
5. Apply pressure with a roller to ensure full adhesion, giving the patch time to cure.
6. Remount the tire.
7. Inflate the tire and test it.

Guide to Tire Patches

What do tire patches look like? Pictured here is the inside of a patched tire.

How long do tire patches take? When done by a tire pro — the whole process, from removing the tire from the rim to inflating and testing — can take about 20 to 30 minutes.  

How long do patches last? Remember, the USTMA doesn't recommend a tire patch alone as a long-term fix. A tire patch-plug combo can last the remaining life of a tire, when installed properly. One factor in how long it lasts is the location of the hole.  

How many patches can a tire have? Tires can have multiple patches and plugs, as long as they aren't too close and the tire remains structurally sound. You should not patch a hole that overlaps another repair. It's time for a new tire.

Can you patch a sidewall? This is a hard no. If the sidewall is damaged or punctured, it's time to replace the tire.

Is a patched tire safe? A patch alone is not USTMA approved, but a properly repaired tire tread (not sidewall) with a patch-plug kit can be safe.  

Is a tire patch permanent? Tire patches are not permanent fixes on their own. Only patch/plug combination repairs are considered permanent. We'll speak more on that later.

How much does tire patching cost? You can patch a car tire yourself relatively inexpensively if you know what you're doing. Some local auto shops might even patch tires for free, in exchange for your repeat business. Professional tire patching can cost $20 to $50 per tire, depending on the tire, the tire's damage, and where you live.

What Are Tire Plugs? Are They Reliable?

Tire plugs are small, sticky rubber strips that can be inserted into a puncture from the outside of the tire. They’re designed to fill the hole and stop air from leaking out. Plugs work best on small punctures in the tread (such as from nails or screws) and can be installed quickly without removing the tire from the rim. Plugs cannot be used on sidewall punctures.

While they’re cheap and fast, plugs are considered more of a temporary or emergency fix. The U.S. Tire Manufacturers Association (USTMA) does not approve plugs by themselves as a safe, permanent repair. For long-term safety, most shops recommend a plug-patch combo instead.

Guide to Tire Plugs

What do tire plugs look like? Pictured here is an example of a tire plug repair kit.

How long do tire plugs last? A plug may hold air for weeks or even months, but it should not be counted on for the full life of the tire. Plugs are temporary fixes. If you want a repair that lasts as long as your tire tread, a plug-patch combo is the way to go.

How many plugs can a tire have? Can you replug a tire twice? There’s no strict limit, but repairs must be in the tread, not overlapping, and spaced far enough apart to keep the tire structurally sound. If punctures are too close together, the tire should be replaced.

Can you plug a hole in or near the sidewall? Again, this is a hard no. Sidewall and shoulder damage can’t be repaired safely. If the hole isn’t in the tread, the tire needs to be replaced.

Is a tire plug safe? Are tire plugs legal? Yes, plugs are legal, but they are not USTMA-approved as permanent repairs. They may work in a pinch, but safety depends on the puncture’s size, location, and the condition of the tire. Any puncture larger than 1/4 inch, or damage to the sidewall or shoulder, requires replacement.

How much does tire plugging cost? Getting a tire plugged costs around $10 to $20 per tire, depending on the vehicle type, tire type and your location. You can do it for less yourself, but we recommend trusting a tire installation professional for patching and plugging tires. 

Are tire plugs safe? Plugs alone are not considered a safe long-term fix. The safest option is a plug-patch combo, which seals both the puncture channel and the tire’s inner liner. Done correctly, that type of repair can last the remaining life of the tire.

Can You Fix Tire Sidewall Damage?

Sidewall damage must be taken seriously. The USTMA specifies that punctures or cuts in the sidewall or shoulder of a tire cannot be repaired. That part of the tire flexes the most and lacks the reinforcement of the tread area, making repairs unwise and unsafe.

The only safe repair area is the tire tread zone, never the sidewall. Many shops use a practical guideline: A puncture must be at least ½ inch away from the edge of the tread to be considered repairable. Anything closer to the sidewall should result in tire replacement. This image shows the tire repair zone:

Even a small nail hole, screw, or cut in the sidewall will worsen over time due to constant flexing and pressure — which can lead to sudden tire failure.

Common questions about sidewall damage

• Is a nail in the sidewall of a tire repairable? No. Time to get a new tire.
• What about a screw in the tire sidewall? No. Replacement is required.
• Can a tire sidewall be repaired? No. Sidewall punctures, tears, or cuts cannot be safely repaired.
• What about plugging tires near the sidewall? Not if the damage reaches the sidewall or shoulder. Only punctures fully within the tread area — generally at least ½ inch from the edge — may be repairable.

Can You Repair a Tire With a Nail?

How do you check for nails in tires? If you suspect you have a nail in your tire, either because you hear a sound that suggests a foreign object is in your tread or because you have a slow leak, make sure your vehicle is in a safe place, away from traffic. Do a visual check for foreign objects, slowly moving the vehicle to inspect all surfaces of the tire. A soapy water test can also reveal slow leaks. 

Should I remove a nail or screw embedded in my tire? Don't remove the nail or screw before you've moved a vehicle to safety. The nail or screw could be serving as a plug to prevent rapid release of air, so don't remove it until it's ready to be fixed.   

How long can I drive with a nail in my tire? This is a tricky question to answer, because it's not unusual to drive with a nail in your tire and not know it! As soon as you know you have a nail or foreign object in your tire, drive only as far as it takes to safely stop. A professional repair technician should remove the nail or screw, otherwise you risk rapid deflation and unsafe driving.

What if the tire has a nail but isn't leaking? Our answer is the same. Drive only as far as it takes to safely stop and either call for roadside assistance or patch-plug the tire (away from traffic). 

A patch/plug repair combination is the best way to fix a tire with a nail, screw or metal shard. The tire plug is put into the hole to stop the leak, and the patch portion seals the damaged area. This is the safest way to fix a tire punctured by a nail or another sharp object.

Flat Tire Fixes: Common Questions Drivers Ask

Who patches tires? Your safest way to proceed with a damaged tire is to speak to a tire professional. They will be able to help you determine the best option, whether that's a simple fix or replacing an old tire with a new one. To find one, we recommend a quick "near me" search for tire repair shops, 

Is it illegal to plug or patch a tire?

Our research uncovered no laws in the U.S. (federal or state) that says plugging a tire is illegal. There are right ways and wrong ways to plug a flat tire -- and industry best practices for when, where and how to plug a flat, but no laws that we are aware of. Refer to the U.S. Tire Manufacturers Association for recommended puncture repair procedures. 

Can my tire be patched? Can a flat tire be fixed?

Yes, a tire may be patched and a flat can be fixed if it meets these criteria: (1) The damage is in what's called the "crown area" of the tire -- the flat surface of the tread that touches the road. (2) A tire professional assesses whether the tire can be repaired and safe to drive on. (3) The location, size and condition of the damage. Tires that have wear bars showing should be replaced.  

What about run-flat tires? Can a run-flat tire be patched or plugged?

Some manufacturers allow for tread-only repairs if the structural integrity is intact and if you don't drive on the tire while flat, but some do not. Check manufacturer guidelines  We cover run-flat tires in a separate post.

Can you plug a tire after using Fix-a-Flat?

Fix-a-Flat is a brand of emergency tire repair that you spray to quickly inflate and seal flat tires. According to the manufacturer, you can repair a tire after filling a hole with Fix-a-Flat. However, many tire professionals will not fix, plug, patch or repair tires that have been treated with Fix-a-Flat because the substance can make repairs unreliable. For that reason, Fix-a-Flat should be treated as a temporary, emergency solution — best used to get you safely off the road or to a shop. Always call your tire shop before using it, and read the instructions carefully so you don’t reduce the chances of a safe, permanent repair. 

How much does it cost to fix a flat or plug a punctured tire?

Obviously the price to plug a tire or patch it depends on where you live and how much damage your tire is. We answer this question with a lot of trepidation, because the average cost to fix a flat is much, much less than the cost of a new tire. The safest repair is always a plug-patch combo, followed by replacing a tire that cannot be repaired. That said, according to Car Shtuff (and a few other sources we checked), the cost to patch a tire averages between $20 and $50.   

Do you have a video that shows how a tire patch works?

This 2-minute video from Consumer Reports explains and shows how tire patches and plugs work, and it also includes safety tips for DIY tire fixes. 

• Illustration 43839281 | Batareykin | Dreamstime.com
• ID 204191847 | Jesada Wongsa | Dreamstime.com
• ID 32568386 | Cristi180884 | Dreamstime.com
• ID 204300201 | Chakraphan Phukhrongthung | Dreamstime.com
• ID 342593213 | Sergii Vasylchenko | Dreamstime.com