# Asphalt emulsion sealer vs cold patch

> Sealer coats a surface at $0.15-$0.30 per sq ft; cold patch fills a hole for a few dollars a bag. Why a hole has to be patched before the driveway is sealed.

Canonical: https://drivewaysealinglab.com/asphalt-emulsion-sealer-vs-cold-patch/

Last updated: 2026-11-09

Asphalt emulsion sealer and cold patch are not competing products. Sealer is a film that protects a sound surface at $0.15 to $0.30 per square foot. Cold patch is bagged asphalt that fills a hole for a few dollars. A driveway with a pothole needs the patch first, because sealer cannot bridge a void.

## Two products, two failures

Asphalt emulsion sealer is a water-based coating of asphalt particles and filler, applied across a driveway to slow oxidation and water entry.

Cold patch is a bagged asphalt mix with a solvent-cut binder, placed without heat to fill a pothole.

Sealer addresses surface ageing. Cold patch addresses lost material. A driveway can have both problems at once, and then it needs both products, in that order.

## Head to head

| Attribute | Emulsion sealer | Cold patch |
| --- | --- | --- |
| Purpose | Protect a surface | Fill a hole |
| Unit | Square foot | Bag, or square foot of hole |
| Cost | $0.15-$0.30 per sq ft | A few dollars per 50 lb bag |
| Coverage | 250-400 sq ft per 5 gal | About 2 sq ft per bag at 2 in |
| Life | 2-3 years | One season to a few years |
| Applied hot | No | No |
| Repairs a base | No | No |
| Order | Second | First |

The life figures are not comparable. A sealer's two to three years is a protective cycle. A cold patch's season is a temporary repair. Neither number says anything about the other product.

## Why sealing over a hole fails

Sealer is a film measured in thousandths of an inch. It cannot span a depression, and it cannot support traffic over a void.

Applied across a pothole, it sags, cures, and breaks under the first tire. The surrounding coat then lifts at the break, and the failure spreads outward from the hole.

The same logic applies to cracks: sealer over an open crack splits along the crack line within a season. Repairs come first.

## Cost of patching and sealing, worked through

A 600 square foot driveway with one 4 square foot pothole and a worn surface:

Hot-mix patch at $250 plus sealcoat at $0.20 per square foot for 600 square feet, $120. Total $370, or $0.62 per square foot.

Cold patch at under $20 plus the same sealcoat: $140 total, but the patch lasts a season and the hole may return.

Over five years, the cold patch route means five bags and five afternoons. The hot-mix route means one patch and two sealcoats at $120 each, so $490 total. By year three the hot-mix route is cheaper in money and far cheaper in time.

There is also a risk cost that does not appear on either invoice. A cold patch that breaks up in a wheel track can throw a piece of asphalt, and a pothole left open through a wet season grows. Neither is priced above, and both are reasons the permanent patch is usually the better purchase on a driveway you intend to keep.

**What neither product can do.**

Cold patch cannot repair a base. If the hole is being reopened from underneath by a soft subgrade or poor drainage, the patch fails regardless of how well it was installed.

Sealer cannot repair a surface. It slows oxidation but does not restore binder that has already gone, and it does not hold raveled aggregate together.

Neither addresses alligator cracking, ponding, or settlement. Those are structural failures, and the honest options are an overlay at $3 to $7 per square foot or replacement at $8 to $15. Our [alligator cracking repair](https://drivewaysealinglab.com/alligator-cracking-repair/) guide covers the diagnosis.

## The sequence that works

1. Diagnose: a hole, a worn surface, or a failing base.
2. If the base has failed, stop and price an overlay or replacement.
3. If it is a hole, patch it properly, squared and compacted.
4. Let the patch settle and firm up before coating.
5. Fill cracks at $2 to $5 per linear foot.
6. Seal the surface at $0.15 to $0.30 per square foot.

Skipping step 1 is how people end up sealing a driveway that needed replacing, or patching a hole that keeps returning because the base is soft.

## When cold patch is the right buy, and what neither can do

Winter emergencies, when hot mix is unavailable and the hole is a hazard.

Temporary access on a property scheduled for replacement.

A stopgap before a permanent patch, where the hole needs to be safe in the meantime.

In those cases the low bag price is doing exactly what it should. It is not a permanent repair, and it is not competing with sealer.

## When sealer is the right buy

A sound surface that has gone grey, with no cracks wider than a hairline and no potholes.

A driveway sealed two to four years ago that is due for its next coat.

A surface where appearance and water shedding matter and the base is stable.

In those cases sealer at $0.15 to $0.30 per square foot is the cheapest maintenance available.

## Reading the driveway instead of the product

The useful question is which failure you have.

Water standing in a depression after rain means the surface is out of plane. Cracks in a connected pattern mean the pavement has lost flexibility. A hole with loose edges means material is being lost, which is cold patch territory.

If two or more are present across a large area, maintenance products are the wrong category. Our [driveway sealing repair](https://drivewaysealinglab.com/driveway-sealing-repair/) guide covers the diagnosis, [potholes repair](https://drivewaysealinglab.com/potholes-repair/) covers the hole-specific options, and [cold patch cost](https://drivewaysealinglab.com/cold-patch-cost/) prices the bags against a permanent patch.