There is no national rule. Massachusetts allows $10 over the estimate, Texas and Arizona have no estimate rule at all, and Wisconsin, New York, California, Connecticut and New Jersey allow nothing without new authorization. The 10 percent figure everyone quotes is the right answer in five of the states checked, close to it in four more, and flatly wrong in the rest.
Start with the correction, because it is the most repeated error in this trade.
New York does not allow you to go 15 percent or $20 over an estimate. That rule is quoted constantly, on forums, in trade articles, in shop training material. The full text of 15 NYCRR Part 82 and VTL §398-d was searched for every percentage and every dollar figure in it. The only percentages in Part 82 concern 10 percent ownership stakes in a business. There is no overage allowance anywhere in either document.
New York is zero tolerance. Any amount above the estimate requires the customer’s consent. The likely source of the confusion: Maryland and Virginia use 10 percent, Virginia allows 20 percent on vehicles 25 years and older, and Massachusetts uses a flat $10.00. Somewhere those blended into a number no state actually uses. If you have been running a 15 percent cushion in New York, you have been running outside the rule.
The short version
- New York’s “15% or $20” rule does not exist. NY is zero tolerance, verified in the full text of 15 NYCRR Part 82 and VTL §398-d.
- Wisconsin is stricter than New York. Zero tolerance, and you may not even proceed if you have reason to believe the price will exceed the estimate.
- Minnesota flips the burden: the written estimate is only owed if the customer asks for one, and the state’s mandatory sign says outright that an oral estimate is not covered by the cost limits.
- Illinois gives customers no right to the replaced parts, the only state among those detailed where that right is absent.
- The spectrum runs from $10 in Massachusetts to no rule at all in Texas and Arizona.
- If you already know the general concept, this is the state-by-state layer on top of it. The basics are in the general 10 percent rule.
Everything below was read in the state’s own statute or administrative code. The 22 states not named here were not researched, and none of this is legal advice. Confirm with your state agency before you set policy.
Auto repair estimate laws by state: the zero tolerance states
Anything above the estimate requires new authorization. No cushion, no rounding.
Wisconsin is the strictest of them and it is not close. Written estimate required above $50, records kept 2 years, and the shop may not proceed once it has reason to believe the final price will exceed the estimate. That is a forward-looking duty: you stop when you expect to go over, not when you actually do. Any software default, training script or shop policy assuming a 10 percent margin in Wisconsin is simply wrong.
New York. Estimate on request with no dollar floor, zero tolerance, records 2 years.
California. Bureau of Automotive Repair rules, zero tolerance, consent required for any amount above the estimate.
Connecticut. Written estimate above $50, zero tolerance, plus a prescribed 24 by 36 inch consumer rights sign in every area where repair orders are written.
New Jersey. Estimate before any service begins, zero tolerance.
The 10 percent states
This is where the folk rule is actually correct.
- North Carolina: written estimate above $350, 10 percent tolerance.
- Maryland: written estimate above $50 on the customer’s request, 10 percent.
- Virginia: written estimate above $25 on request, 10 percent, and 20 percent for vehicles 25 years and older.
- Ohio: written estimate above $50, 10 percent, sales tax excluded.
- Utah: written estimate above $50, 10 percent.
Note the thresholds. Virginia’s obligation kicks in at $25, North Carolina’s at $350. Same tolerance, fourteen times the trigger.
The capped and hybrid states
These use a percentage and a dollar limit, and the interaction is where shops get it wrong.
Colorado. Written estimate always, no floor. Overage allowed is 10 percent or $25, whichever is less. On an $800 job, that is $25, not $80. The Motor Vehicle Repair Act of 1977 governs, and the “whichever is less” is doing enormous work.
Nevada. Written estimate above $50. Overage 20 percent or $100, whichever is less. Records 1 year.
Michigan. Written estimate above $50. Overage is the lesser of 10 percent or $50. Records kept 3 years. Michigan also licenses both the shop and the mechanic, which is covered in do you need a license to open an auto repair shop.
Florida. Written estimate above $150, not $100 as commonly written. Overage $10 or 10 percent, whichever is greater, capped at $50. Fla. Stat. 559.905.
Hawaii. Written estimate always. Overage 15 percent if the estimate is under $100, 10 percent if over. Records 2 years.
Massachusetts. The tightest dollar figure in the country: $10.00 over the estimate triggers reauthorization. Records 18 months.
The “110 percent” states
Washington requires a written estimate above $100 and permits the final bill to reach 110 percent of the estimate, excluding sales tax. That reads like 10 percent and mostly behaves like it, but the sales tax exclusion is written into the text and it matters on a large ticket.
Minnesota also uses 110 percent, above a $100 threshold, and then does something no other state does.
Minnesota inverts the burden, and says so on a sign
In most states the shop owes a written estimate once the job crosses a threshold. In Minnesota, the written estimate is owed only if the customer asks for one, and the state’s mandatory posted notice tells customers exactly what that costs them: “An oral estimate is not subject to the above repair cost limitations.”
A Minnesota customer who does not request a written estimate has no cost protection at all. For a shop, that is not an invitation, it is a warning sign. Working off oral estimates because the state permits it is how you end up in a dispute with no documentation and a customer who is genuinely surprised.
The states with no rule at all
Texas and Arizona have no estimate or reauthorization requirement. None. No repair statute in either state caps what you bill against the estimate. What Texas does require, and nobody mentions, is that repair records be kept 1 year. In Arizona nothing was found at all: no license, no estimate rule, no records rule.
Read that carefully, because no sector statute is not the same thing as anything goes. General consumer protection law still applies. In Texas that is the Deceptive Trade Practices Act, Business & Commerce Code Chapter 17, and it works after the fact rather than through a percentage ceiling: there is no number to stay under, only a bill you may have to defend. A $400 quote billed at $1,900 is a complaint waiting to happen.
This is where legal and defensible come apart. A Massachusetts shop that goes $11 over without a call has broken a rule. A Texas shop that triples an estimate has no repair statute to answer to and will still lose the customer, the review, and the referral. Nothing in the Texas code stops a credit card chargeback either.
Pennsylvania hands the number to the customer
Pennsylvania requires written authorization and then lets the customer set the ceiling. Illinois offers a variant: 10 percent, or a limit the customer specifies. Arguably the cleanest model in the country, because the number is negotiated up front rather than inherited from a statute.
Illinois: no right to the old parts
Worth flagging because it runs against the grain. Across the states detailed here, customers generally have some right to the replaced parts, in one of three designs: offered automatically, in Maryland, Virginia and Michigan; only on request, in New York (in writing before work begins), New Jersey, Connecticut, Pennsylvania and Massachusetts; or waived by signature, as on New Jersey body shop estimates.
Illinois has no such right. The full text of 815 ILCS 306 was searched and it is absent. Illinois is the one state among those detailed where the customer has no statutory claim to the parts you took off.
What to do with all of this
Four things, and they work in every state including the two with no rules.
1. Write the estimate. Always. The states with no requirement are where written estimates protect you the most, because there is no statute to argue about, only documents.
2. Set your internal ceiling below your state’s. If your state allows 10 percent, call at 5. Thirty seconds, and it turns a surprise into a decision the customer made.
3. Log the authorization. Not “he said go ahead.” Date, time, who you spoke to, what they approved, the new figure. In Wisconsin and New York, where there is no tolerance at all, that record is the only thing between you and a violation. Whether it lives in a management system or a notebook matters less than that it exists and can be found two years later.
4. Know your records retention. Michigan 3 years. New York, Hawaii, Wisconsin, Illinois, Rhode Island 2 years. Massachusetts 18 months. Washington, Nevada, Minnesota, Texas 1 year.
If you are an AAA Approved Auto Repair shop, AAA requires authorization above 10 percent regardless of state, plus a minimum 24 month / 24,000 mile warranty and one ASE Master technician. In a zero tolerance state, the stricter rule governs.
Frequently asked questions
Can a mechanic legally charge more than the estimate?
It depends entirely on the state. Massachusetts allows $10 over. Colorado allows 10 percent or $25, whichever is less. Wisconsin, New York, California, Connecticut and New Jersey allow nothing without new authorization. Texas and Arizona have no rule at all.
Is the 10 percent rule real?
In some states. North Carolina, Maryland, Virginia, Ohio and Utah use 10 percent. Others use a different number or a cap, and several use zero. Applying 10 percent nationally will put you outside the rule in a large share of the country.
Does New York allow 15 percent over the estimate?
No. That figure circulates widely and appears nowhere in 15 NYCRR Part 82 or VTL §398-d. New York requires consent for any amount above the estimate.
What happens if a shop goes over the estimate without approval?
In states with a limit, the customer generally cannot be required to pay the excess, and the shop may face a consumer protection complaint. Even in Texas and Arizona, the practical outcomes are chargebacks, unpaid balances and public reviews.
Bottom line
The estimate rule is not a national standard with local variations. It is twenty-odd different rules that happen to share a vocabulary, and the most widely quoted one, New York’s 15 percent, is not real.
Find your state above, set your internal call-the-customer threshold below whatever the law allows, and keep the authorization record for as long as your state requires. Done that way the state line stops mattering, because your process is already stricter than the strictest rule on this page.
Nothing here is legal advice. Confirm with your state agency before you set policy.
Related reading: do you need a license to open an auto repair shop · auto repair estimate template · shop supply fees explained
