How to Add Uninsured Motorist Coverage to an Existing Policy
Uninsured and underinsured motorist protection can often be added to an active auto policy without replacing the entire policy. The change may be issued through an endorsement, with new limits, an effective date, a premium adjustment, and updated policy documents.
NAIC reports that 15.4% of U.S. motorists were uninsured in 2023 [1]. The Insurance Research Council separately reports that 33.4% of drivers were either uninsured or underinsured that year [2], which helps explain why UM and UIM can matter even when liability insurance is widely required.
NAIC explains that an endorsement can add or modify coverage on an existing auto policy and may be issued mid-term or at renewal. Once the change is made, the endorsement becomes part of the insurance contract and can affect the premium [3].
What Uninsured Motorist Coverage Adds to Your Policy
Uninsured motorist coverage is designed to help when another driver causes a covered accident but has no liability insurance. Depending on state rules and your policy, it may also apply to certain hit-and-run accidents. Underinsured motorist coverage applies when the at-fault driver has insurance, but their limits are too low to cover your losses.
NAIC explains that uninsured motorist coverage reimburses you if an uninsured or hit-and-run driver hits you, while underinsured motorist coverage pays when the at-fault driver’s coverage is not enough to pay your total loss [4].
UMBI
Uninsured motorist bodily injury may help with covered medical bills, lost wages, pain and suffering, and related injury damages for you and passengers.
UIMBI
Underinsured motorist bodily injury may help when the at-fault driver has liability insurance, but not enough to pay the full covered injury claim.
UMPD
Uninsured motorist property damage may help repair your vehicle in some states, though availability and deductibles vary.
How to Check Whether You Already Have UM Coverage
Before adding anything, review your declarations page. Look for labels such as “Uninsured Motorist Bodily Injury,” “Underinsured Motorist,” “UM/UIM,” “UMPD,” or “Uninsured Motorist Property Damage.” Some policies list UM and UIM separately, while others combine them.
If you do not see the coverage, ask your insurer whether you previously rejected it, whether your state requires a signed rejection form, and whether you can add it mid-policy. You should also ask whether adding the coverage changes only the premium or also requires a new policy endorsement.
Where to look
Check your declarations page, policy endorsements, online account coverage summary, renewal offer, or quote documents.
What to confirm
Confirm bodily injury limits, property damage limits, deductibles, stacking rules, hit-and-run rules, and whether UIM is included.
Step-by-Step: How to Add UM Coverage to an Existing Policy
Adding uninsured motorist coverage is usually straightforward, but the details matter. You want the correct coverage type, appropriate limits, clear effective date, and written proof that the change was added.
Review your policy
Check your current limits, deductibles, state-required coverage, and whether UM/UIM already appears on your declarations page.
Request options
The insurer’s UM/UIM quote details should show the available coverage types, limit choices, and resulting premium change before the endorsement is accepted.
Choose limits
The UM/UIM limit options determine the maximum protection available for a covered claim, so per-person and per-accident amounts should be checked before the change is finalized.
Confirm in writing
Ask for the effective date, updated declarations page, endorsement, total premium change, and payment impact.
How Much Does It Cost to Add Uninsured Motorist Coverage?
The added premium depends on the state, insurer, selected limits, driver profile, and the types of UM/UIM protection chosen. Forbes Advisor reports average annual costs of $136 for UMBI, $90 for UIMBI, and $36 for UMPD in its analysis [5].
Your actual quote may be higher or lower. The important comparison is the premium increase versus the possible cost of medical bills, lost wages, repairs, deductibles, and legal recovery efforts after a crash with an uninsured or underinsured driver.
| Coverage added | Typical purpose | Cost factor to review |
|---|---|---|
| UMBI | Helps with covered injuries when an uninsured driver causes the accident. | Limit per person and per accident. |
| UIMBI | Helps when the at-fault driver has insurance but not enough liability coverage. | Whether UIM is separate, combined, or automatically included. |
| UMPD | May help repair your vehicle after a covered uninsured-driver accident. | Availability, deductible, and whether collision coverage overlaps. |
| Higher UM/UIM limits | Provides more protection after serious injuries or larger losses. | The cost difference between UM/UIM limit levels shows how much additional premium is tied to a higher claim ceiling. |
How UM/UIM Limits Change the Policy Addition
The selected limits define how much protection is being added to the active policy. A low-limit endorsement and a higher-limit endorsement are materially different policy changes, even when both appear under the same UM/UIM label.
Limit factors to consider
- Your state’s minimum UM/UIM requirements.
- Your bodily injury liability limits.
- How many passengers you regularly carry.
- Your health insurance deductible and out-of-pocket maximum.
- Your savings cushion after a serious accident.
- Your income and risk of wage loss after an injury.
- Whether you live in an area with higher uninsured-driver risk.
Do not compare only the monthly price
A low-cost add-on with very low limits may not provide enough protection after a serious crash. Ask for several limit options and compare the annual cost difference before deciding.
State Rules Can Change Your Options
UM/UIM rules are state-specific. Some states require the coverage, some require insurers to offer it, and others allow rejection or different limit selections. NAIC notes that auto insurance requirements and coverage rules vary by jurisdiction [6].
This is why two drivers in different states may see very different options. One driver may have UM automatically included unless rejected, while another may need to ask for it as an optional add-on.
Required states
Your policy may need UM/UIM limits that meet state rules before the policy can be issued.
Offer-required states
The insurer may need to offer UM/UIM, but you may be allowed to reject or choose different limits.
Optional states
You may need to request the coverage and compare available limits, deductibles, and premium changes.
UM Coverage vs. Collision, Health Insurance, MedPay, and PIP
Uninsured motorist coverage does not replace every other coverage. It works differently from collision, comprehensive, medical payments, personal injury protection, and health insurance. Understanding the difference helps you avoid gaps and duplicate assumptions.
| Coverage | What it may help with | Important limitation |
|---|---|---|
| UMBI | Covered injuries, lost wages, and related damages after a covered uninsured-driver accident. | Usually does not repair your car unless property damage coverage is included separately. |
| UMPD | Vehicle damage caused by an uninsured driver in states where it is available. | May have a deductible and may not be available in every state. |
| Collision | Damage to your vehicle after a crash, regardless of whether the other driver is insured. | Usually requires a deductible and does not cover bodily injury. |
| Health insurance | Some medical treatment costs after an injury. | May not cover lost wages, pain and suffering, passengers, or vehicle damage. |
| MedPay or PIP | Medical expenses and sometimes related costs, depending on state and policy. | Coordination with UM/UIM varies by state and insurer. |
When Added UM Coverage Can Matter More
The financial effect of added UM/UIM protection can be larger for drivers who spend more time on the road, regularly carry passengers, have limited emergency savings, or would face meaningful income loss after an injury.
Strong reasons to add it
- You regularly carry family members or passengers.
- You drive in high-traffic areas.
- Your state has a high uninsured-driver rate.
- You could not easily absorb medical bills or lost wages.
- You want protection beyond another driver’s liability coverage.
Questions before declining
- Would health insurance cover all accident-related costs?
- Could you afford lost income after an injury?
- Would collision coverage repair your car?
- Does your state require a written rejection?
- Would low limits be enough after a serious crash?
How to Confirm the Policy Change Was Added Correctly
After you request uninsured motorist coverage, do not rely only on a phone conversation. Ask for written confirmation. Your updated declarations page should show the added coverage, selected limits, effective date, premium change, and any deductible that applies.
| Document or detail | Why it matters | What to verify |
|---|---|---|
| Updated declarations page | Shows the official coverage listed on your policy. | UMBI, UIMBI, UMPD, limits, vehicles, and drivers. |
| Effective date | Confirms when the added coverage begins. | No gap between request and active coverage. |
| Premium change | Shows how much the add-on changes your bill. | Monthly, six-month, and annual total cost. |
| Endorsement | Explains the policy change and any special terms. | Exclusions, deductibles, stacking rules, and claim conditions. |
| Rejection form | Important if you previously rejected UM/UIM coverage. | Whether a new selection or signed form is required. |
How a UM Claim Usually Works
If you are hit by an uninsured driver, the claim usually starts with reporting the accident to your insurer. You may need to provide police information, photos, medical records, repair estimates, witness details, and any proof that the other driver had no insurance or left the scene.
Report quickly
The UM/UIM claim process generally begins with prompt notice to the insurer and a request for the documents needed to evaluate coverage and damages.
Document the loss
Save photos, medical bills, repair estimates, police reports, claim numbers, and letters from insurers.
Follow deadlines
Policy deadlines, state claim rules, and proof requirements can affect whether a claim is accepted.
FAQ: Adding Uninsured Motorist Coverage
Can I add uninsured motorist coverage to my existing policy?
Usually yes, but availability depends on your insurer, state rules, current policy, and whether UM/UIM was previously rejected. Contact your insurer and ask for a quote to add the coverage.
Does uninsured motorist coverage pay for car repairs?
Only if your policy includes uninsured motorist property damage and your state allows it. Otherwise, collision coverage may be the coverage that helps repair your vehicle after a crash.
Is uninsured motorist coverage required?
It depends on your state. Some states require it, some require insurers to offer it, and others allow drivers to reject it or choose optional limits.
How much does it cost to add uninsured motorist coverage?
The cost varies by insurer, state, driver profile, and selected limits. Forbes Advisor lists average annual costs of $136 for UMBI, $90 for UIMBI, and $36 for UMPD, but your quote may differ.
Should my UM limits match my liability limits?
Many drivers compare UM/UIM limits with bodily injury liability limits. Matching them can be a practical starting point, but your budget, state rules, passengers, income, and savings also matter.
Will adding UM coverage change my whole policy?
It usually adds an endorsement or updates your declarations page. Ask for written confirmation showing the new limits, effective date, premium change, and any deductible.
Final Thoughts
Adding UM/UIM to an existing policy is mainly a contract-change process: the coverage type, limits, effective date, premium adjustment, and applicable forms all need to be reflected in the policy documents.
The completed change should be visible on the endorsement or updated declarations page. If those documents do not match the requested coverage, the insurer should clarify the policy status before a loss occurs.
References
- National Association of Insurance Commissioners, Uninsured Motorists, including the 15.4% nationwide uninsured-motorist estimate for 2023. Source↩
- Insurance Research Council, Uninsured and Underinsured Motorists: 2017–2023, including the 33.4% combined uninsured-or-underinsured estimate for 2023. Source↩
- National Association of Insurance Commissioners, guidance on adding an endorsement or rider to an existing insurance policy, including mid-term policy changes and premium effects. Source↩
- National Association of Insurance Commissioners, auto coverage guidance including uninsured and underinsured motorist coverage definitions. Source↩
- Forbes Advisor, Uninsured Motorist Coverage, including average annual cost estimates for UMBI, UIMBI, and UMPD. Source↩
- National Association of Insurance Commissioners, Auto Insurance consumer information, including state-based coverage and insurance-regulation context. Source↩