EPA and CARB Emissions Rules for Gas Mowers

Quick Overview

The EPA sets national rules for new gas mower engines. CARB sets tougher rules just for California. Since 2024, CARB has blocked the sale of new gas mowers there (EPA, 2008; CARB, 2021).
You can still own, use, and fix a gas mower you already have. This is true in every state. No law makes you scrap a working machine.
California’s rule only stops the sale of new gas mowers. It does not ban the use of mowers bought before 2024.
One hour with a gas mower can make more smog than a car does over several hundred miles. This comes from CARB’s own test data (CARB, 2021).
Other states are watching California’s rule. None have copied it in full as of mid-2026. Some do offer rebates for switching to electric.

What Are the EPA and CARB Gas Mower Rules?

The EPA sets rules for new gas mowers. These rules cap smoke and fuel leaks. The rules got tough in 2008 (EPA, 2008). CARB is a state group. It works in California only. CARB’s rules are tougher than the EPA’s rules. Since 2024, most new small engines sold there must run clean. That group covers mowers, blowers, and trimmers (CARB, 2021).

These are two different rule sets. Keep them apart in your mind. The EPA rule covers all 50 states. It caps how much smoke a new mower can make. The CARB rule covers one state: California. It goes one step past the EPA rule. It stops stores from selling new gas mowers at all. If you live outside California, this stop does not touch you. But it still shapes what factories build for the whole U.S.

I have fixed small engines for four years. My shop is in Milan. I hear this mix-up a lot. Owners think their mower got banned. It did not. The rule stops new sales. It does not touch the mower in your garage right now.

The EPA’s National Small Engine Rules, Explained Simply

The EPA rule covers small gas engines. This means engines under 25 horse power. Mowers, trimmers, and chainsaws are all in this group (EPA, 2008). The rule sets two kinds of caps.

Smoke caps. New engines must cut two bad gases. These are called hydrocarbons and nitrogen oxides. To hit this goal, many brands added a new part. It is called a catalytic converter. This was the first time small engines used this part (EPA, 2008).

Fuel leak caps. New mowers must also stop fuel gas from leaking out. This is why new fuel tanks feel thick. Fuel caps now seal tight too.

These caps went into full use between 2010 and 2012 (EPA, 2008). Every gas mower built for U.S. sale since then meets them. You do not have to do a thing. The maker checks the engine first. This happens long before it reaches a store shelf.

What This Means If You Own an Older Mower

Nothing changes for you. The EPA rule targets makers, not owners. A mower built in 2005 stays fully legal. You can own it, run it, and fix it in any state. No federal rule forces you to retire old equipment.

CARB’s Zero-Emission Rule and California’s New-Sale Ban

CARB changed its rule in 2021. This is the version in the news now. Starting with model year 2024, most new small engines sold in California must run clean (CARB, 2021). In plain words: stores there can no longer sell new gas push mowers. The same goes for most gas riding mowers, leaf blowers, and trimmers.

[IMAGE PLACEHOLDER: Retail garden equipment aisle in California showing shelves of battery-powered mowers with a “zero-emission” signage placard]

A few key facts get lost in the news on this. Here they are, in plain terms:

It stops sale, not use. You can still run a gas mower you own. This is true for as long as it works. CARB says there is no rule that makes you toss out old gear (CARB, 2021).
Fix-it work stays legal. You can still fix your gas mower. A new carb, a new blade, a new plug – none of that is blocked. Only new sales are hit.
Generators move slower. Portable generators face a new fuel rule in 2024. They must run fully clean by 2028 (CARB, 2021).
A private sale is not a store sale. The rule hits makers and stores. If you sell your own mower to a neighbor, this rule does not apply. Buying used through a shop may fall under other rules. Check with your county first.

Why CARB Moved on This

CARB built this rule on real test data. One hour with a gas mower can make as much smog as a 300-mile car drive (CARB, 2021). Now scale that up. Americans spend close to three billion hours a year on lawn work (EPA, 2007). Add it up, and small engines turn into a real air problem. This is true even though one single mower looks small on its own.

I see the reason for this each week in my shop. Small mower engines lack the clean-air parts a car has. There is no strong catalytic converter at work. There is no chip that tunes the fuel mix as you mow. These engines burn fuel dirty, by design. That same trait makes them cheap and easy to fix – which is why so many folks still pick gas.

Does Your State Follow California’s Rule?

As of mid-2026, no other state copies CARB’s full clean-sale rule for gas mowers. A few states, like Washington and New York, floated like bills. None have passed a matching law yet. [VERIFY: confirm current legislative status in Washington and New York before publishing, since bills move fast]

Many states offer a smaller step: cash-back or trade-in plans. These pay you to swap a working gas mower for a new electric one. California runs its own plan. It is called the Clean Off-Road Equipment Voucher Incentive Project. This plan mainly aids small lawn care firms (CARB, 2021). If you live outside California, check your city or county site. Some local air boards run small cash-back plans too. This is true even in states with no full sales ban.

Jurisdiction	Gas Mower Rule Status (2026)	Applies To
Federal (EPA)	Exhaust and fuel vapor limits on new engines since 2011-2012	All new mowers sold in the U.S.
California (CARB)	New-sale ban on gas-powered small off-road engines since 2024	New retail sales only, not existing ownership
Most other states	No matching sales ban as of 2026	The EPA rule still applies here
Select cities/counties	Local rebate or trade-in programs	Varies by program

What This Means If You’re Buying a Mower Right Now

If you live in California, your new-mower picks are now mostly battery ones. This is true for most push and riding mowers under the horse power cutoff. If you live in any other state, gas mowers are still fine to buy new. They still meet the EPA’s rule.

Legal status is not the only thing to weigh, though. Here is what shifts day to day with a battery mower vs. a gas one. This comes from what I see at my shop counter:

Upkeep costs drop. No carb to clean out. No plug to swap. No yearly oil change. I still see gas mowers come in each spring with a stuck carb. Old fuel sat in the tank all winter. A battery mower has no part that fails this way.
The price tag is higher. A solid battery push mower runs about $400 to $700 at retail in 2026. A like gas model runs $250 to $450. [VERIFY: current price ranges close to publish date, since retail pricing shifts with seasonal sales]
Run time is the real trade-off. Most battery mowers cut a quarter- to half-acre yard on one charge. After that, you need a spare pack or a break to charge. A gas mower just gets a fill-up and keeps going.

Common Mistakes Owners Make About These Rules

Thinking the ban hits them too. This is the top thing I hear at the shop counter: “So I can’t use my mower now?” You can. The rule stops new sales in California only. It does not touch a mower you own, in any state.

Mixing up their state with California. News posts and social feeds blur state lines a lot. Unless you live in California, the EPA’s rule is the one that fits you – not CARB’s tighter one.

Thinking old mowers can’t be fixed. Shops like mine fix pre-2024 gas mowers every day. No rule blocks fix-it work on gear you already own.

Mixing up “clean” with “gas mowers are gone for good.” CARB’s rule hits new sales today. It says nothing about the used-gear market. It says nothing about parts, which stay easy to find for now.

Total Cost of Ownership: Gas vs. Battery Under the New Rules

Some folks want to know if a switch pays off now, even outside California. Here is a five-year cost guess for a typical quarter-acre yard:

Cost Factor	Gas Push Mower	Battery Push Mower
Purchase price	$250-$450	$400-$700
Yearly fuel or charging cost	$40-$60 in gasoline	$5-$10 in electricity
Yearly routine upkeep	$30-$60 (oil, plug, filter, blade)	$10-$20 (blade only)
Typical major repair by year five	Carburetor or starter, $60-$120	Battery pack swap, $100-$180
Estimated five-year total	$550-$950	$625-$1,000

The real gap is small. Ads make it look big. Battery mowers win on quiet, easy use. They do not always win on flat cost, once you add a future battery swap.

A Quick Timeline of Gas Mower Emissions Rules

Readers often ask how we got here. This short list shows the key steps:

1990 – CARB adopts its first small off-road engine rule, the base version later updated in 2021 (CARB, 2021).
2008 – The EPA proposes tighter national exhaust and fuel vapor rules for small engines, including mowers (EPA, 2008).
2010-2012 – The EPA’s tighter rules take full effect. Every new mower sold in the U.S. must comply from this point on (EPA, 2008).
2021 – CARB approves its updated rule, setting a 2024 zero-emission sales target for most small off-road engines (CARB, 2021).
January 2024 – California retailers stop selling new gas-powered mowers, blowers, and trimmers under the horsepower cutoff (CARB, 2021).
2028 – Portable generators in California must meet a full zero-emission standard, the last piece of CARB’s phase-in (CARB, 2021).

Frequently Asked Questions

Is it illegal to own a gas lawn mower in California?

No. You can own and use a gas mower you already have in any state, even California. CARB’s rule only stops the sale of new gas mowers, starting with 2024 models (CARB, 2021). Your mower is fine.

Can I still buy a gas mower in California?

You cannot buy a brand-new gas mower from a store there as of 2024. CARB now says new small engines sold there must run clean (CARB, 2021). Buying used from a person is not hit by this rule, though local rules can shift, so check first.

Will the EPA ban gas mowers nationwide?

Not right now. As of mid-2026, the EPA caps smoke from new small engines. It has not put out a full sales ban like California’s. A change like that would need a whole new rule process.

Does the CARB rule apply to riding mowers and zero-turns?

Yes, for units under the 25-horse power cutoff. That covers most home riding mowers. Bigger work-grade units past that cutoff fall under other EPA rules.

Can I still get parts to repair an old gas mower?

Yes. Parts for pre-2024 gas mowers are still easy to find. This holds true through both dealer shops and third-party sellers. No rule blocks the sale of fix-it parts for gear you already own.

Do these rules affect commercial landscapers differently than homeowners?

The new-sale rule works the same way for both groups. The gap shows up in aid plans. CARB’s cash-back plan aims at small lawn firms. It helps cut the cost of a switch (CARB, 2021).

Do I need to register or report my gas mower under these rules?

No. Neither the EPA nor CARB asks owners to sign up a mower or file forms. The check step happens at the plant, long before the mower reaches a store.

What to Do Next

If you live in California and your gas mower is near the end, start pricing battery ones now. Do not wait for it to break down. Cash-back plans and stock shift year to year. If you live in any other state, nothing has changed for you. Just budget for the same clean-air mower you would have bought anyway. Either way, keep your mower’s guide book and its metal label close at hand. That label is the fast way to check which rules fit your engine.