How to Read and Use Loss Runs for Commercial Insurance Renewals

Loss runs are the most important document in a commercial insurance renewal. They are the historical record of every claim filed against a policy — dates of loss, amounts paid, reserves on open claims, and current status — and underwriters use them as the primary input for pricing decisions, eligibility determinations, and coverage restrictions. A broker who can read a loss run fluently, identify anomalies, and present loss history in the most favorable defensible light is significantly more effective at renewal than one who forwards raw documents and waits for quotes. This guide covers how to request loss runs, what every column means, how to analyze the pattern of losses, and how to use that analysis to manage submissions and renewal outcomes.

What Loss Runs Are and Why Underwriters Require Them

A loss run report is a document generated by an insurance carrier listing all claims submitted under a policy or group of policies during a defined period. For most commercial lines — general liability, commercial property, commercial auto, umbrella — underwriters require three to five years of loss runs before quoting a renewal or a new submission. Workers' compensation experience rating uses exactly three years of paid and incurred losses, excluding the most recent policy year because loss development on recent claims is not yet complete.

Loss runs serve two purposes for the underwriter. First, they establish the actual loss ratio for the account — total incurred losses divided by earned premium — which is compared against the carrier's target loss ratio to determine whether the existing rate is adequate. Second, they reveal claim characteristics that frequency counts and premium comparisons do not: whether large losses are isolated events or a pattern, whether open reserves are stale and potentially under-reserved, and whether the client has taken meaningful steps to address recurring exposures.

Without loss runs, a carrier will either decline to quote or apply an assumed worst-case loading that inflates the renewal premium. Producing clean, complete loss run documentation is the broker's first competitive advantage in the renewal process. For a detailed explanation of how carriers move from raw loss data to a renewal quote, see the loss ratio and renewal pricing guide.

How to Request Loss Runs

Loss runs must be requested from the current carrier, not the client. Clients do not receive automatic copies of their loss run reports, and even when clients have prior reports on file, they are typically outdated and do not reflect recent activity or reserve changes on open claims.

Who to request from: Most carriers allow the named insured or their authorized agent (broker of record) to request loss runs. If you are not currently the broker of record — for example, when attempting to market an account away from a competitor — you need a signed authorization from the named insured before the carrier will release the report.

Lead time: Request loss runs no fewer than 90 days before renewal. Some carriers respond within 48 hours through self-service portals; others take 10–15 business days for manual requests. Surplus lines carriers and program administrators may take longer. Factoring in the time needed to analyze the report, build the submission narrative, and solicit competitive quotes, 90 days is a minimum — 120 days is better for large or complex accounts.

What to request: Ask for five years of loss runs on each line of coverage, including current valuation (reserves updated to within 30–60 days of your request date). If the account has had multiple carriers for different lines or policy periods, request runs from each carrier. A three-carrier GL history with gaps is a red flag underwriters will ask about.

Format: Request PDF or Excel export if available. Excel format allows you to sum columns, filter by claim type or line, and calculate loss ratios without manual transcription. Some carriers provide both; always ask for machine-readable format when available.

How to Read a Loss Run Report

Loss run formats vary by carrier, but every report contains the same core data elements. Understanding each column is necessary to identify issues before forwarding the report to underwriters.

Date of loss: The date the loss event occurred — not the date the claim was reported, not the date of payment. Underwriters count losses by the policy period in which the loss occurred. A claim reported in 2025 for an event that happened in 2023 appears in the 2023 policy year.

Date reported: The date the insured notified the carrier of the claim. The lag between date of loss and date reported is a data point: large lags may indicate poor risk management practices or, in workers' compensation, delayed injury reporting which tends to correlate with higher ultimate claim costs.

Claim status (Open/Closed): Open claims have active reserves — the carrier's estimate of future payment to settle the claim. Closed claims have no remaining reserve; the total paid is the final cost. Open claims are particularly important at renewal because reserves can increase before the claim closes, and an open claim with a large reserve will remain in the loss run data until it is settled.

Amount paid: What the carrier has actually disbursed — indemnity payments to the claimant plus allocated loss adjustment expenses (ALAE) such as defense attorney fees, expert witnesses, and investigation costs. In general liability and umbrella lines, ALAE can equal or exceed indemnity in litigated claims.

Reserve: The carrier's current estimate of future payments on open claims. Reserve adequacy is a judgment call, and underwriters apply their own development factors when the reserve seems low relative to the claim type. A GL claim showing $500 in paid and a $250,000 reserve signals active litigation or a severe injury.

Incurred: Paid + Reserve = Total Incurred. This is the number underwriters use to calculate the loss ratio for a policy period. For an open claim, total incurred is a projection, not a final number.

Claim description: Free-text field describing the cause of loss. Review these carefully — generic descriptions like "liability" or "property damage" are less useful than "customer slip-and-fall, fractured hip, litigation pending." When submitting to underwriters, you may supplement or clarify claim descriptions to ensure the context is accurate.

Analyzing Loss Patterns: Frequency vs. Severity

Once you can read individual loss run columns, the next skill is pattern analysis across the full history. Underwriters care about two distinct problems:

High frequency / low severity: Many small claims indicate a systemic operational issue — a slip-and-fall hazard, a recurring vehicle incident pattern, a process that generates consistent minor property damage. Frequency losses are more predictable than severity losses, which means underwriters load for them directly in the rate. A client with 15 GL claims averaging $3,000 each over five years is often harder to place competitively than a client with one $25,000 claim over the same period.

Low frequency / high severity: One or two large claims can drive a high loss ratio, but if the cause is isolated (a single catastrophic event, a terminated employee, a one-time premises condition), the severity may be more defensible than the loss ratio suggests. A client whose five-year GL loss ratio is 120% because of one $400,000 settled slip-and-fall — and who has since resurfaced the parking lot and installed new lighting — has a different risk profile than a client whose 120% loss ratio comes from 30 recurring incidents.

When analyzing loss patterns, calculate:

• Loss ratio by policy year (not just overall) — a worsening trend concerns underwriters more than a flat or improving trend at the same level
• Frequency count by line — total number of claims per year, not just dollar amounts
• Open claim proportion — what percentage of incurred losses are reserves on open claims versus settled amounts

Building the Submission Narrative

Loss runs do not tell the story of what happened or what changed. That narrative is the broker's job to create, and it is often the difference between a renewal with a competitive rate and one that markets poorly.

A submission narrative for an account with adverse loss history should address three questions explicitly:

What caused the losses? Underwriters want a plain-language explanation of each significant claim. For GL, describe the incident, the claimant, whether liability was disputed, and the resolution. For property, describe the cause and what the settlement covered. Do not let a $150,000 loss run line speak for itself — provide context.

What has changed? The most credible loss narrative is one paired with documented risk management improvements. If a client had three vehicle accidents in 2023 and subsequently implemented GPS monitoring, hired a fleet safety coordinator, and added backing cameras to all vehicles, say so explicitly and attach supporting documentation where available. Underwriters are more receptive to adverse history when they can see a credible break in trend.

Why is the trend improving (or not worsening)? If loss runs show deterioration, acknowledge it and explain why the trajectory will change. If loss runs show improvement, highlight it prominently — a declining frequency trend in the most recent two years deserves a heading in the submission, not a footnote.

The same submission narrative that helps your current carrier maintain terms is the one that gives alternative markets enough information to quote competitively. For strategies specific to large premium increases, see how to handle a client whose renewal premium increased 30% or more.

Loss Runs and Workers' Compensation: The Experience Mod Connection

For workers' compensation, loss runs interact directly with the experience modification rate — the e-mod that multiplies the manual premium up or down based on actual versus expected losses. The rating bureau (NCCI in most states) uses three years of loss run data, excluding the current policy year, to calculate the e-mod.

Two factors affect how losses impact the e-mod:

Primary vs. excess losses: In the e-mod formula, the first $17,000–$18,000 (the primary threshold, which varies by state and year) of any single claim is the "primary" loss and carries full weight. Loss dollars above the primary threshold are "excess" and receive a much lower weighting. This means that one $500,000 catastrophic injury affects the e-mod far less, dollar-for-dollar, than 30 claims that each hit the primary threshold. Frequency costs disproportionately more than severity in workers' comp rating.

Open claim reserves: Reserves on open claims appear in the loss run at full incurred value — the carrier's current estimate of what the claim will ultimately cost. If a claim closes for less than the reserve, the e-mod is recalculated downward in the subsequent year. Brokers can sometimes work with carriers to review reserves on claims that appear over-reserved relative to current medical and legal status, potentially accelerating closure and reducing the reported incurred value before the rating period closes.

For a complete breakdown of how workers' comp audits affect payroll classifications and premium, see the workers' comp premium audit guide.

Using Loss Runs for Remarketing

When remarketing an account to alternative carriers, loss runs are the first document every underwriter will request. Present them proactively rather than waiting to be asked — attaching current loss runs to the initial submission signals a prepared, transparent broker and removes a follow-up round from the quoting process.

Several practical points for remarketing submissions:

• Order loss runs before you know you're remarketing. The 90-day lead time means that waiting until a client calls about their renewal premium leaves you with inadequate time to conduct a meaningful market survey. Request runs during the annual review for any account where adverse history or a hardening market creates renewal uncertainty. See the annual insurance review guide for how to build this into the client service cycle.

• Reconcile gaps. If you have loss runs from three carriers over five years, make sure the policy periods are contiguous. A gap — even a short one — is a yellow flag for underwriters who may assume a carrier declined to renew and refused to provide loss runs. Address gaps in the cover letter with a factual explanation (e.g., "client was previously insured under an owner's personal policy during this period" or "carrier merged and loss history is available from the acquiring company").

• Include large-claim summaries. For any loss over $25,000, attach a one-paragraph claim summary with the submission. Underwriters at alternative markets who lack the context of your account's history will read raw loss data through a conservative lens. A claim summary that explains a resolved large loss in accurate, complete terms is a legitimate and expected part of a professional submission package.

FAQ: Loss Runs and Commercial Renewals

Can I request loss runs if I'm not yet the broker of record?

Yes, but only with a written authorization signed by the named insured. Most carriers accept a signed Loss Run Request Letter (sometimes called an Experience Request or Authorization for Release of Loss Information). The letter must be on the insured's letterhead or signed by an authorized officer, authorizing the carrier to release loss run data to a named agent. Without this authorization, carriers will not release the report.

How current should loss runs be at submission?

Underwriters typically require loss runs valued within 60–90 days of the submission date. A loss run valued as of six months ago understates current reserves and may not reflect developments on open claims. Request a fresh valuation whenever you are within the 60-day window of submission, even if you received a prior run a few months earlier.

What does it mean when a claim shows zero paid and a large reserve?

A zero-paid, large-reserve claim is typically in early litigation or investigation. The carrier has received the claim and established an opening reserve based on the alleged injury or damage, but no settlement payment has been made. These claims are often the most dangerous items in a loss run because the reserve may be conservative (early-stage claims are frequently reserved low until liability develops) or because the matter is actively litigated with an unpredictable outcome. Flag these explicitly in your submission narrative and provide whatever context you have on current claim status.

What is ALAE and how does it affect the loss ratio calculation?

Allocated loss adjustment expenses (ALAE) are the direct costs the carrier incurs to investigate and defend individual claims — attorneys, expert witnesses, court reporters, and investigators whose work is tied to a specific claim. ALAE is typically included in incurred losses for general liability and umbrella, which means it increases the loss ratio. Some carriers report ALAE separately; others fold it into the paid amount. When comparing loss runs across carriers, verify whether ALAE is included to ensure your loss ratio calculations are consistent.

Can a carrier refuse to provide loss runs?

No. Most state insurance regulations require carriers to furnish loss run reports to the named insured or their authorized agent within a specified timeframe — typically 10–21 business days — upon written request. The National Association of Insurance Commissioners (NAIC) model regulation and most state-level versions prohibit carriers from withholding loss runs as a retention tactic. If a carrier delays or refuses, escalate through your state department of insurance complaint process.

How do insureds sometimes manipulate loss runs?

The most common manipulation is suppressing claims — paying small losses out-of-pocket rather than filing them with the carrier to keep the loss run clean. This can reduce the reported loss ratio but also means the client is self-insuring small losses, potentially creating an unreported aggregate that underwriters do not see. A very clean loss run for a large account — zero or near-zero losses over five years with high revenue and significant operations — sometimes warrants a closer look at whether the carrier's policy had broad coverage or whether losses were routinely absorbed internally.

What if a large claim closes after the renewal binds?

If a claim that was reserved at a large amount closes for significantly less before the renewal year closes, many carriers will provide a premium adjustment or consider the improved history at mid-term or the subsequent renewal. Build this expectation into the client relationship when presenting renewal terms: a reserved open claim is not the same as a final paid loss, and a favorable resolution materially improves the account's future pricing position.

Arvori helps insurance brokers organize submission documentation, track loss history trends across a client portfolio, and identify accounts approaching renewal with adverse loss development — so the annual service cycle surfaces the right accounts for proactive outreach. Learn how Arvori supports commercial lines brokers.