Methodology for the Uninsured / Underinsured Motorist (UM/UIM) Dataset

The ru3.us UM/UIM Dataset (Version 2025.01) is a structured representation of uninsured and underinsured motorist coverage requirements derived from an initial consolidated 2025 reference document.

This page explains what the dataset does and does not claim to represent, and how it should be used.

Scope and Intent

The dataset answers two core questions for each jurisdiction:

Does the initial reference text explicitly describe UM or UM/UIM as required?
Where UM/UIM is described, what are the stated minimum limits?

It does not attempt to independently re-derive full UM/UIM law for each state. Instead, it:

Preserves the text as given where requirements are stated.
Flags all other jurisdictions as "unknown" to avoid incorrect inferences.

This makes Version 2025.01 a partial but honest representation of UM/UIM requirements.

Fields and Interpretation

Each row includes:

state_code – Two-letter USPS abbreviation.
state_name – Full state name.
um_uim_required –
- "yes" if the initial source text clearly describes UM or UM/UIM minimums as part of the mandatory coverage package.
- "unknown" if the initial source text does not describe UM/UIM requirements at all.
um_uim_limits_text –
A plain-text description of the UM/UIM minimums where specified. Examples include:
- “$25,000 uninsured/underinsured motorist coverage per person; $50,000 uninsured/underinsured motorist coverage per accident.”
- “$25,000 uninsured motorist coverage per person; $50,000 uninsured motorist coverage per accident; $25,000 uninsured motorist property damage coverage.”
notes –
- Typically: “UM/UIM requirements not specified in initial source text; may be optional, not mandated, or omitted.”
- May be expanded in future versions where regulator or statutory sources clarify the status.

Data Sources

Version 2025.01 uses:

The same consolidated 2025 state-by-state requirements text that underpins the minimum liability dataset, which includes:
- Liability minimums
- PIP / MedPay provisions
- UM/UIM details for some states
No additional external sources at this stage.
- States where UM/UIM requirements are not described in that text are not filled from secondary online sources in this version.

Future versions (e.g., 2025.02 and beyond) may:

Incorporate regulator or statutory checks for every jurisdiction.
Convert "unknown" entries into "yes" / "no" with precise limits where appropriate.

Design Choices

Key design decisions:

Avoiding false certainty
Where the source text is silent on UM/UIM, the dataset uses "unknown" rather than assuming “not required.”
Text-first representation
Because UM and UIM are frequently grouped and have property damage components in some states, Version 2025.01 stores a single um_uim_limits_text field rather than trying to normalize multiple numeric columns prematurely.
Separation from liability dataset
UM/UIM is maintained in its own dataset to:
- Keep the primary liability dataset simple and consistent.
- Allow independent evolution as UM/UIM rules are validated and expanded.

Future Enhancements

Planned improvements include:

Breaking out:
- um_bi_per_person
- um_bi_per_accident
- um_pd_per_accident
- Separate UIM fields where applicable
Resolving "unknown" entries through:
- Direct statute review
- Regulator bulletins
- Official consumer publications

Each major update will result in a new dataset version with a changelog describing:

Which states were updated
How the requirements were validated
Any structural changes to fields

How to Use This Dataset

You can use this dataset to:

See which states, per the initial reference, clearly document UM/UIM minimums.
Compare patterns where UM/UIM is bundled with liability or PIP requirements.
Build internal tools that treat "unknown" properly as “needs further review.”

You should not use this dataset as a sole, authoritative statement of UM/UIM law in any jurisdiction. Always confirm requirements with:

State insurance regulators
Statutes
Insurers or qualified legal counsel