Paint Bubbling on a Car

Updated September 29, 2026

Car paint bubbles when rust grows on the metal underneath, or when moisture, solvent or grease is trapped in the paint layers during a repaint. Sherwin-Williams calls the second kind blistering, and says it can appear months after painting. Bubbles from rust need the metal treated; paint-layer bubbles need the area removed and refinished.

Below, a table sorts each bubble type by cause, a second table lines up repair costs from AAA, Kelley Blue Book and two cost guides by severity, and a short verdict says which path fits which situation.

What causes paint to bubble on a car?

Rust under the paint and a problem during painting are the two causes the sources describe. A mechanic answering a question about a 2010 Chevrolet Equinox on YourMechanic said the cause was likely a problem with the undercoating or clear coating, "allowing moisture to get in and cause the rust or bubbling."

The second starts in the paint booth. Sherwin-Williams’ refinish troubleshooting guide defines blistering as "Swelled areas appearing as pimples or bubbles in the topcoat film, often months after application." Its listed causes include moisture trapped beneath the paint film, "Improper dry time of undercoats before topcoating," and "Painting over grease, oil or rust."

How can you tell rust bubbles from paint-application bubbles?

Start with the panel’s history, then the bubble’s look and location. A panel that was repainted recently points toward a paint-application cause, since Sherwin-Williams notes blistering can show up "often months after application." ThePricer warns that "a quarter-size bubble may hide corrosion along a door seam, behind a wheel-arch liner, or inside a rocker panel." If the paint looks faded rather than blistered, see car paint oxidation.

Numbered steps for a first look:

1. Note whether the panel has ever been repainted. If so, say so when you get a quote.
2. Photograph each bubble. Consumer Reports advises owners to "Photograph and track them."
3. Check whether the bubbles cluster near seams, edges, chips or scratches, or spread evenly across the panel.
4. Have a body technician inspect. ThePricer notes that "a rust bubble can hide damage several times larger than the visible spot," so what shows on the surface understates what is underneath.

Can heat or contamination cause paint bubbles?

Both can, during painting. PPG lists "Bake temperature too high or IR lamp too close to the surface" among the causes of solvent pop, and "Using too fast of a reducer and/or hardener for the spray conditions." Contamination shows up as fisheyes, which Sherwin-Williams traces to "Spraying over surfaces contaminated with oil, wax, silicone, grease, etc." Humidity matters too: the Sherwin-Williams guide lists "Spraying in extreme high humidity conditions" as a cause of trapped moisture.

These are workmanship or process causes in a fresh repaint.

What happens if you ignore bubbling paint?

The damage grows and the repair bill grows with it. Consumer Reports states that "paint problems can spread and become increasingly expensive to fix." The same article warns owners not to "risk a small problem spreading and exposing bare metal to the elements and inviting rust." AAA says the same in fewer words: "paint damage can lead to costly problems like rust if ignored."

CarParts.com adds a practical detail: "A vehicle with exposed steel is prone to rusting if driven in the rain or snow."

How do you fix bubbling paint by severity?

The fix scales with how deep the damage goes. Paint-application blisters are treated by removing and refinishing. Sherwin-Williams’ repair instruction for blistering is "Remove affected area and refinish," and "Extreme cases must be stripped to bare substrate before refinishing." Before a refinish, compare single-stage and two-stage paint.

Rust bubbles add a metal stage. ThePricer’s tiers run from a small cosmetic surface spot, to bubbling or perforated rust on one body-panel area, to jobs that need cutting, welding, panel replacement, paint blending and corrosion protection. A rust converter is one product class made for this work: Sherwin-Williams describes its Mar-Hyde One-Step Rust Converter as one that "permanently converts rust into a hard, black primer sealer." ThePricer cautions that "Coating active rust without proper preparation can hide progression rather than stop it," so treat a converter as one step in a repair, not a cover-up.

How much does it cost to fix bubbling paint?

Published ranges for bubbling rust run from a few hundred dollars to about $1,500 per body-panel area, and climb past $5,000 when metal work is involved. Each figure below is what the publisher printed, for the repair it names.

CarXplorer reports that in professional rust repair "labor costs often account for 70-80% of the final bill." Kelley Blue Book notes that "Prepaint repairs to address peeling, delaminating, rust, dents, cracks, and scratches are essential for a flawless finish and add to the overall expense." For repainting the whole car, see our guide to the cost to paint a car.

Is it worth fixing early?

Yes, because paint problems can spread. ThePricer’s tiers show how the price climbs as the damage goes deeper, from $100 to $400 for a small cosmetic surface spot to $1,500 to $5,000 or more for cutting and welding work.

If a paint problem shows up on a newer car, Consumer Reports advises: "Work with your dealership if your vehicle is still under warranty. Otherwise, consult a body shop, which can assess the problem and suggest options".

How do you prevent paint bubbling?

Prevention splits into what the painter controls and what the owner controls. For painting, Sherwin-Williams’ prevention list says to "Allow undercoats to thoroughly dry/cure before topcoating" and to "Clean and prep substrate using recommended products and procedures." It also recommends allowing "additional flash time between coats and/or add retarder when spraying in humid conditions."

For owners, the lever is speed. Treat chips and scratches before bare metal sits exposed, and photograph anything that changes. Whoever paints a panel should be asked how the surface was prepped and cured before topcoat, since those steps are exactly what the paint-maker guides list.

Which path fits your situation?

If the panel was repainted recently and no rust shows, ask about a refinish-only repair; if rust shows, ask about a rust repair. A shop should tell you which one applies before quoting. If a quote does not say whether the metal underneath was checked, ask.

For a car with one small rust spot, AAA prices rust repair at $150 to $500 per affected area, listed among the repairs done before painting. For bubbling across several panels or a car with perforation, expect a bigger repair or a repaint.

For texture problems that look like bubbles but are a dimpled, bumpy surface, see orange peel in car paint, which is a different finish defect.

Common questions

Can I pop the bubbles myself? Leave them alone and have the panel looked at first. If the paint peels away, CarParts.com warns that "A vehicle with exposed steel is prone to rusting if driven in the rain or snow."

Will the bubbles come back after a repaint? They can if the cause was not removed. Sherwin-Williams lists "Painting over grease, oil or rust" as a blistering cause, so the surface underneath has to be clean and rust-free before topcoat.

Is a rust converter enough on its own? Not by itself. ThePricer notes that "Coating active rust without proper preparation can hide progression rather than stop it."

Can a new car get paint bubbles? Yes. Consumer Reports reports that some models develop "bubbles, peeling, and flaking."

Bottom line: Bubbles on a repainted panel can be a paint-application problem fixed by refinishing; bubbles that show rust need the metal treated, and Consumer Reports warns paint problems "can spread and become increasingly expensive to fix."

If you are near Rowlett, Texas, Accelerate Auto Repair and Collision (3002 Century Dr, Rowlett, TX 75088; (469) 501-5115) does paint and bodywork with ASE Master Certified and ASE-certified technicians. One thing to know before any shop repaints a panel: the collision warranty at Accelerate Auto Repair and Collision covers "the collision work it performs," which the warranty lists as "bodywork, parts, and paint," and it also states: "Lifetime warranty strictly excludes any claims related to rust or corrosion. Coverage does not apply to surface rust, rust perforation, or corrosion resulting from pre-existing conditions, aging underlying metal, rock chips, road salt, or exposure to inclement weather and harsh environmental conditions." Ask any shop what its warranty says about rust. See our paint jobs page for the service.