If you are asking what insurance company has the highest claim denial rate because you want to know which dental carrier to blame, there is no published answer. No federal agency, state regulator or trade group ranks dental carriers by denial rate. The only comparable, public denial rates in US insurance come from CMS marketplace transparency data on individual medical plans, and those numbers say nothing about how your dental claims are adjudicated. The number that matters is the denial rate inside your own practice, broken out by carrier and by CDT code.
That is an unsatisfying answer, so here is the useful version of it: what the public data actually measures, why it cannot be applied to dentistry, and how to build the ranking you were looking for out of your own remittances in an afternoon.
Where the published denial rate numbers actually come from
Almost every "denial rates by insurance company" chart circulating online traces back to one source: issuer level transparency reporting for qualified health plans sold on the individual marketplace. Insurers report claims received and claims denied, and researchers publish the resulting percentages by company.
Three things about that dataset matter before you quote it in a team meeting.
It covers individual market medical plans. Employer sponsored coverage, which is where most dental benefits live, has no equivalent public reporting requirement. Standalone dental plans are largely outside it too, with some state exchanges publishing dental issuer data separately.
The definitions are not standardized. One issuer may count a front end rejection as a denial, another may not. One may count claim lines, another whole claims. Rates quoted in published analyses commonly range from single digits to above 30 percent across issuers, and a meaningful slice of that spread is definitional rather than behavioral.
Most denials in that data are administrative. Duplicates, wrong payer, member not found, service not covered by this plan. Medical necessity denials, the category everyone pictures, are typically a small minority of the total.
| Public source | What it actually measures | What it will not tell you |
|---|---|---|
| CMS marketplace transparency reporting | Claims received and denied, by issuer, for individual market plans | Anything about employer dental plans, and nothing at the procedure level |
| NAIC complaint database and complaint index | Complaints closed against a company relative to its market share, by line of business | Denial rate, since a complaint is a consumer action rather than an adjudication outcome |
| State insurance department market conduct reports | Findings against a named insurer in one state | Comparable, current, dental specific numbers across states |
| Carrier published statistics | Whatever the carrier chose to publish | Anything audited to a common definition |
| Your own remittance files | Every denial you received, by carrier, group, provider and CDT code | Anything about carriers you do not bill |
Only the last row is measured the way a dental practice needs it measured.
Who is considered the worst insurance company?
There is no official designation, and the phrase almost always comes from lists that rank auto and home insurers on litigation and settlement behavior. For dental and health lines, the closest thing to an objective US measure is the NAIC complaint index. Each company gets a number where 1.00 is the median for its line of business and its share of the market. A 2.40 means the company drew more than twice the complaints its size would predict.
It is a real signal and it is free to look up by company and line. It is also not a denial rate. A carrier can deny a great deal and generate few complaints if patients never appeal, and a carrier can generate complaints over billing and network issues while adjudicating cleanly.
The deeper problem with ranking carriers is that plan provisions are bought by the employer, not set by the carrier. Two groups administered by the same national carrier can carry different frequency limits, different waiting periods, different missing tooth language and different alternate benefit provisions. One group pays your D4341 without a murmur and the other wants full mouth probing depths attached. Same carrier name, same clearinghouse, opposite outcomes.
Which is why the unit of measurement in a practice should be carrier plus employer group, not carrier. That distinction alone usually explains most of what staff describe as a carrier being difficult.
Which company is no. 1 in claim settlement?
No US authority publishes a claim settlement ranking for dental carriers. What does exist is a legal floor and a set of metrics you can compute yourself.
The legal floor is your state's prompt payment law. As of this writing most states set a deadline for paying or denying a clean claim, commonly in the 30 to 45 day range for electronic submissions, with interest accruing after. The deadline, the definition of clean, and the interest rate are all set state by state, and they change, so confirm the current rule with your state insurance department rather than relying on a number in an article.
The metrics are these four. Compute them per carrier and per group, monthly.
| Metric | Formula | A workable target |
|---|---|---|
| First pass resolution rate | Claim lines paid on first submission, divided by lines submitted | Commonly quoted as 90 percent or better |
| Denial rate | Lines denied, divided by lines adjudicated | Commonly quoted as under 5 percent |
| Days to payment | Mean calendar days from submission to remittance posting | 14 to 30 days for electronic dental claims, varies widely by carrier |
| Appeal overturn rate | Appeals paid, divided by appeals filed | Above 50 percent means your denials were largely preventable |
That last metric is the one practices skip and the one that pays. A high overturn rate is not a compliment to your appeals writer. It is evidence that the claim should have gone out differently the first time.
What insurance company has the best reputation for paying claims?
Reputation and reimbursement are different variables, and they are not strongly correlated. Consumer satisfaction surveys ask members about customer service, ID cards and call center wait times. None of that predicts what lands on your remittance.
The comparison that matters is net dollars collected per procedure, after denials and after the contractual write off. Here is illustrative arithmetic on 100 crowns, code D2740, with an office fee of 1,400 dollars at both carriers.
| Carrier A | Carrier B | |
|---|---|---|
| Contracted allowable for D2740 | 780 | 1,020 |
| Crown lines submitted in the year | 100 | 100 |
| Lines denied on first pass | 3 | 11 |
| Denials recovered on appeal | 2 | 8 |
| Lines ultimately paid | 99 | 97 |
| Allowed dollars collected | 77,220 | 98,940 |
| Appeals written | 3 | 11 |
Carrier B denies crowns at almost four times the rate and still produces about 21,700 more allowed dollars on the same volume. The cost of the difference is eight extra appeals, and at a commonly quoted 20 to 45 minutes each, that is roughly four extra hours of staff time across a year.
Denial rate on its own is a bad ranking variable. It only becomes useful next to the allowable. Our guide to maximizing dental insurance reimbursement rates covers how to pull the allowable side of that comparison out of your fee schedules.
What is Allstate's claim denial rate?
Allstate does not publish one, and neither does any regulator on its behalf. It is known primarily as a property and casualty insurer writing auto and home coverage, and it is not a carrier most dental offices bill as a primary dental plan, so its name in a denial rate chart is usually a sign the chart is about a different industry.
The wider point transfers, though. No US insurer in any line is required to publish a company wide claim denial rate. Property and casualty complaint data is available by line of business through the NAIC, and individual states publish market conduct findings, but neither is a denial rate and neither is comparable across companies. Any specific percentage attached to a specific carrier name in a general search result is either drawn from marketplace medical data, estimated, or invented.
The denial rate that runs your practice is your own
Most practices that try to compute a denial rate get a number that is wrong in the same four ways.
Count lines, not claims. A four line claim with one denied line is not a denied claim. Line level counting is also the only way CDT patterns surface, and the pattern is the actionable part.
Keep patient responsibility out of the numerator. Lines carrying group code PR with reason 1, 2 or 3 are deductible, coinsurance and copay. They are the plan working correctly. Counting them can double your apparent denial rate.
Keep contractual adjustments out of the numerator. CO-45, charge exceeds the fee schedule or maximum allowable, is your write off, not a denial. It appears on nearly every in network line.
Separate soft denials from hard ones. A request for information is a pause. A non covered service is a stop. They need different work queues and they should not share a metric.
Use a fixed measurement window so late remittances do not distort the picture: claims submitted in one calendar month, measured 60 days later.
Once the number is clean, the reason codes tell you where the work belongs.
| Reason code | What it says | Where it is actually preventable |
|---|---|---|
| CO-16 | Claim lacks information or has a submission or billing error | Submission. Tooth number, surface, quadrant, arch |
| CO-18 | Exact duplicate claim or service | Follow up. Check status before resubmitting |
| CO-27 | Expenses incurred after coverage terminated | Verification. Re-verify on the day of service |
| CO-29 | Time limit for filing has expired | Accounts receivable. Track each plan's filing window |
| CO-50 | Not deemed a medical necessity by the payer | Documentation. Narrative and radiographs at submission |
| CO-96 | Non covered charge | Verification. Category exclusions, read before treatment |
| CO-97 | Included in the payment for a service already adjudicated | Coding. Bundling rules differ by plan |
| CO-119 | Benefit maximum for this time period has been reached | Verification. Remaining maximum at the time of the estimate |
| CO-151 | Payer deems the information does not support this many services | Verification. Frequency limits per code |
| CO-197 | Precertification or authorization absent | Scheduling. Predetermination before the appointment |
Read down the right hand column and the theme is hard to miss. Most of what practices experience as carrier behavior was decided before the claim was sent. Our breakdown of the top reasons for dental insurance claim denials goes through each pattern with the fix attached.
Build the carrier ranking you actually wanted
Six steps, one afternoon, no new software required.
- Export 12 months of remittance detail at line level. Fields you need: carrier, employer group, date of service, CDT code, billed, allowed, paid, reason code, group code.
- Define the denominator as adjudicated lines. Exclude front end rejections that never reached adjudication, since those are a clearinghouse problem measured separately.
- Define the numerator as lines paid at zero for a reason other than PR or CO-45. That is your denial count.
- Group by carrier plus employer group, with a floor of 30 adjudicated lines. Below 30, you are measuring noise and will act on it.
- Sort by dollars denied, not by rate. A 25 percent rate on 40 sealant lines is 10 denied lines at a small allowable. A 4 percent rate on 600 restorative lines is 24 denied lines at several times that allowable, so it is the larger problem despite the better rate.
- Take the top three reason code and CDT pairs and fix the upstream cause. Then re-measure at 90 days.
If the appeal overturn rate on those pairs is high, the denials were preventable at verification or submission, and the fix belongs upstream rather than in the appeal queue. Can AI prevent dental insurance claim denials covers what pattern detection can and cannot do here. For anything you do have to appeal, how long you have to appeal a dental claim denial has the deadlines, which are shorter than most offices assume.
Where a bad carrier is really a bad submission
A few denial categories get blamed on the carrier almost every time and are usually ours to fix.
Frequency denials, CO-151, come from counting the patient's history across all providers rather than only visits in your chart. A prophy at another office six weeks ago still consumes the interval.
Downgrades are not denials at all. The claim pays, at the rate of a cheaper acceptable alternative, and the difference lands on the patient. If nobody compares the allowed amount to the estimate, it gets written off silently.
Coding level challenges arrive when a code is defensible clinically and unsupported by the note. That is a documentation gap that looks like an adjudication dispute. Our guide to overcoming a dental claim denial for upcoding works through the evidence that changes those outcomes.
Orthodontic denials sit in their own category, with lifetime maximums, age limits and banding date rules that behave differently from medical or basic restorative benefits. Disputing a dental insurance denial for braces covers those specifics.
What to do with the ranking you came here for
Keep the question, drop the national scope. The carrier with the highest denial rate in the United States is unknowable and would not change a single thing you do on Monday. The carrier plus group combination with the highest denial rate in your practice is knowable this week, and it will point at three or four fixable causes that are costing real money.
Curo reads the reason codes off every remittance as it posts, groups denials by carrier, employer group and CDT code, and routes the preventable ones back to verification instead of into an appeals pile. If you want to see the denial patterns in your own data rather than in a national chart, denial management is where that work lives.
One last thing worth saying plainly. When a practice finally measures this properly, the usual finding is not a villain. It is two or three employer groups with an unusual frequency rule, one code that keeps going out without the attachment it needs, and a filing window someone mistook for 365 days. None of that appears in a ranking of insurance companies. All of it appears in your remittances, and it has been there the whole time.