NCCI's Tennessee advisory filing TN-2026-04 proposes a 4.8% increase to voluntary loss costs and an identical 4.8% increase to assigned risk rates, with a proposed effective date of October 1, 2026 for new and renewal policies (NCCI, June 2026). The increase does not reflect deteriorating claim experience; the Tennessee WC system is operating within normal parameters. It reflects a single regulatory event: the April 1, 2026 update to the Tennessee Medical Fee Schedule, which reset maximum allowable physician reimbursement to the 2026 national Medicare Conversion Factor of $33.4009, effective through March 31, 2027 (Tennessee Bureau of Workers' Compensation, April 2026). The filing is pending regulatory approval; final figures will be confirmed in a separate NCCI approval circular.

4.8%
Proposed average Tennessee WC loss cost increase from NCCI filing TN-2026-04, driven by the April 2026 medical fee schedule update, not from deteriorating claim experience
$33.4009
National Medicare Conversion Factor effective April 1, 2026 through March 31, 2027, the anchor for Tennessee WC physician reimbursement rates under the updated fee schedule
Oct 1
Proposed effective date for new and renewal policies under TN-2026-04, pending Tennessee Commissioner of Commerce and Insurance approval

A Law-Only Filing: What the Actuary Skips and Why

Standard advisory loss cost filings run through NCCI's full ratemaking cycle: historical loss data organized by accident year, development of losses to ultimate using loss development factors, selection of prospective medical and indemnity severity trends, credibility weighting of state versus countrywide experience, and a final off-balance adjustment. The process builds a loss cost indication from observed claim behavior, projected forward. A law-only filing eliminates all of that.

TN-2026-04 is designated a law-only filing because the cost driver is a regulatory action, not a shift in claim frequency, severity, or development patterns. When a state legislature or regulatory body changes a fee schedule, changes compensability, or modifies benefit levels, NCCI isolates the cost impact of that specific legal change and files it separately, outside the normal experience cycle. The distinction matters for both the regulator reviewing the filing and the underwriter applying the resulting loss costs: the 4.8% captures one thing only, and that thing is the physician fee schedule change. Utilization patterns, claim frequency, and indemnity costs are untouched by this filing and will flow into the next experience-based ratemaking cycle on their normal schedule.

From tracking how law-only filings interact with experience-based cycles, the sequencing creates a real pricing lag. Once TN-2026-04 takes effect October 1, 2026, the new loss cost level becomes the baseline against which future Tennessee experience is measured. If the fee schedule change also shifts utilization patterns, or if the effective reimbursement change is larger or smaller than NCCI's estimate, that signal will not surface until experience data from post-amendment accident years matures and enters the next standard filing. The law-only indication is necessarily a forward estimate made at the moment of regulatory change, not a verification against observed paid losses.

Tennessee's Medicare Link and the $33.4009 Conversion Factor

Tennessee ties its workers compensation medical fee schedule directly to the CMS Physician Fee Schedule, using a multiplier structure layered over the national Medicare rates. The April 2026 fee schedule handbook sets maximum allowable physician reimbursement at 200% of the national Medicare Physician Fee Schedule for most general medicine, evaluation and management, and surgical codes; orthopedic surgeons and neurosurgeons certified by a recognized specialty board are compensated at 275% of Medicare for surgical procedures (Tennessee Bureau of Workers' Compensation, April 2026). Physical and occupational therapy is capped at 180% of Medicare; radiology at 200%; laboratory at 180%.

The national Medicare Conversion Factor is the dollar figure that translates relative value units into payment amounts across the entire Medicare fee schedule. CMS sets it annually. For the period April 1, 2026 through March 31, 2027, the CMS nonqualifying conversion factor is $33.4009 (CMS, CY 2026 Physician Fee Schedule Final Rule). The prior period rate was $32.3465 (April 1, 2025 through March 31, 2026), a change of approximately 3.26% at the factor level. Because Tennessee applies a 200% multiplier over Medicare rates for most physician codes, any movement in the conversion factor flows through at full scale to the WC maximum allowable rates. The 3.26% factor change becomes a 3.26% shift in the maximum allowable reimbursement ceiling for physician services covered under Tennessee WC.

The gap between 3.26% at the conversion factor level and 4.8% at the total advisory loss cost level is where the actuarial work lives.

From Conversion Factor to Loss Cost: The Payment-to-Fee-Schedule Bridge

Maximum allowable reimbursement is a ceiling, not a transaction price. Actual WC medical payments in Tennessee sit below the fee schedule cap for a portion of the provider population, particularly where insurer network contracts negotiate discounts below the statutory maximum. NCCI's actuarial step is to estimate the effective net cost impact after accounting for the distribution of actual payments relative to the fee schedule maximum. This ratio, commonly called the payment-to-fee-schedule ratio (P/FS), is typically below 1.0 and varies by service category and provider type. In states with strong network contracting, the P/FS ratio can discount the nominal fee schedule change significantly before it reaches actual paid loss costs.

The second adjustment is the service category weight. Tennessee's WC medical cost base is not homogeneous; it is a blend of physician professional services, hospital outpatient care, hospital inpatient admissions, pharmacy, and ancillary services such as physical therapy, chiropractic, and durable medical equipment. The April 2026 fee schedule update affects physician services at 200% of Medicare and therapy at 180% of Medicare; it does not directly revise hospital inpatient per diem rates, which Tennessee sets on a fixed-dollar basis ($2,347 per day for surgical admissions in the first seven days, $1,932 per day for medical admissions, $4,725 per day for Level 1 trauma admissions, unchanged in the April 2026 handbook). Pharmacy reimbursement is governed separately by AWP-plus-dispensing-fee rules.

The weighted, P/FS-adjusted medical cost impact is then multiplied by medical's share of total WC costs (medical versus indemnity), yielding the total advisory loss cost percentage change. At the system-weighted average, that arithmetic produces 4.8%. Because physician services drive a large share of Tennessee WC medical spend and Tennessee's 200% multiplier means the conversion factor change flows through at full scale, the calculation is relatively direct once the P/FS discount and service category weights are applied. The 4.8% average is the endpoint; the actuarial derivation is in the weights and the discount factors.

Class Code Dispersion Behind the 4.8% Average

The system-wide average does not distribute uniformly across class codes. Tennessee, like all NCCI states, prices WC by classification, and the medical-to-total cost ratio varies substantially by industry and job type. The law-only filing translates the fee schedule change into medical costs first; the share of total loss costs that are medical then determines how much of the medical cost change carries through to each class code's total loss cost indication.

Consider two class codes at the extremes of the medical cost spectrum. Class 8810 (clerical office employees) is indemnity-heavy by nature; these are desk workers whose injuries, when they occur, typically involve musculoskeletal strains and repetitive stress conditions that produce more lost-time days per claim than they produce physician service volume. A reasonable estimate for medical as a share of total losses in clerical codes is 35 to 40%. Applied to an 8.7% medical-cost-level change implied by the weighted calculation at 55% average medical cost ratio, clerical loss costs would increase by roughly 3.1 to 3.5%, materially below the 4.8% system average.

Class 5537 (carpentry, not otherwise classified) sits at the opposite end. Construction codes carry physician-intensive loss profiles, with musculoskeletal injuries, laceration repairs, fracture management, and post-surgical physical therapy driving medical cost ratios of 65 to 70% of total losses in many states. At those levels, the same 8.7% medical cost-level change translates to a total loss cost increase of approximately 5.7 to 6.1%, a full percentage point or more above the system average. For a carpentry account with $500,000 in current annual premium, the difference between a 4.8% and a 6.1% loss cost change is $6,500 in annual premium before the carrier's loss cost multiplier loading.

Healthcare workers (class codes in the 8000 series), light manufacturing (class codes in the 3000-4000 range), and construction trades generally will see above-average effective changes. Retail, clerical, and professional service codes will see below-average changes. The filing's single stated figure of 4.8% is the starting point for account-level analysis, not the ending point.

Account-Level Pricing: Applying the Revision Across a Mixed Book

For an underwriter or pricing actuary working through renewal accounts straddling the October 1, 2026 effective date, the procedure is straightforward but requires attention to class code composition. The loss cost revision applies to the advisory loss cost component of the manual premium calculation. The carrier's loss cost multiplier (LCM), which loads for underwriting expenses, profit, assessment charges, and policyholder dividends, is not changed by TN-2026-04; it applies to the revised loss cost as it did to the prior one.

A two-class account split between clerical and carpentry payroll illustrates the composite effect. If a contractor carries $2 million in carpentry payroll and $500,000 in clerical payroll, the weighted loss cost revision is not simply 4.8%; it is the payroll-weighted blend of the class-specific revisions. At an estimated 5.8% for carpentry and 3.2% for clerical, and with carpentry representing 80% of the total payroll, the blended revision is approximately 4.97%, a full 17 basis points above the system average because the book skews toward the physician-intensive class. Running the system average uniformly across a carpentry-heavy account underestimates the premium impact.

Experience modification factors and schedule rating credits adjust the manual premium after the loss cost revision is applied; they do not offset the fee schedule change at the loss cost selection stage. An account with a 0.85 experience modification entering renewal still gets the 0.85 applied to a higher manual premium base.

The October 1 Transition Window

The October 1, 2026 effective date creates a mid-year transition for agents quoting renewals in the August-September window. Policies renewing before October 1 carry the current loss costs; policies renewing on or after October 1 carry the revised loss costs, assuming regulatory approval is confirmed and the NCCI approval circular is published before that date. The practical implication: an account renewing September 30 is quoted under one set of advisory costs and an otherwise-identical account renewing October 1 is quoted under a 4.8%-higher set. Agents placing large accounts with significant Tennessee payroll exposure should track the approval timeline carefully.

A second transition question applies to mid-term endorsements. If a policyholder adds Tennessee-exposed payroll mid-term after October 1, 2026 on a policy that started before that date, the applicable loss cost depends on the carrier's endorsement treatment and state filing. Carriers whose policy forms incorporate advisory loss costs by reference at the policy effective date may handle this differently than carriers that apply the current approved loss cost to mid-term additions. This is a policy-form and filing question, not a ratemaking question, but it warrants communication to agency staff processing Tennessee audits and payroll additions in the fourth quarter.

Medical Severity Context: The 4.8% Is Not the Full Medical Cost Story

TN-2026-04 captures one cost driver: the fee schedule step change. It does not capture the ongoing medical severity trend that layers cost pressure on top of fee schedule adjustments. NCCI's 2026 State of the Line reported that WC medical claim severity grew 4% in 2025, and that severity growth exceeded the WC Weighted Medical Price Index, the fee-schedule-weighted measure of medical price inflation (NCCI, 2026 State of the Line). The gap between severity growth and the medical price index indicates that utilization growth, specifically increased inpatient and specialty service volumes, is now driving WC medical costs faster than fee schedule prices alone.

This matters for Tennessee pricing beyond TN-2026-04. The law-only filing establishes a new cost baseline as of October 1, 2026. The next experience-based filing for Tennessee will incorporate actual paid losses from accident years that straddled the fee schedule change, trend them forward, and develop a new indicated loss cost level. If medical utilization continues to outpace the price index during that experience period, the next experience-based indication will reflect both the fee schedule step change and the underlying utilization trend. Pricing actuaries should not read 4.8% as the complete medical severity picture for Tennessee workers compensation. The fee schedule change is a discrete, quantifiable event; the utilization trend is a continuous process that compounds with each accident year in the development window.

NCCI's 2026 State of the Line also noted that inpatient utilization is now a more prominent medical cost driver than in prior years, across all WC states (NCCI, 2026 State of the Line). Tennessee's fixed-dollar hospital inpatient per diem rates provide partial protection against this driver, but complex surgical admissions that run long in duration can still accumulate significant cost despite the per-diem cap, particularly in trauma cases where the $4,725 daily rate applies. The law-only filing does not touch the inpatient per diem structure; that component remains governed by the current handbook rates and will not change unless the Bureau of Workers' Compensation amends those separately.

Further Reading

Sources

P&C Insurance Actuarial Pricing Loss Reserving

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