SIBTF qualification calculator
California’s Subsequent Injuries Benefits Trust Fund pays workers whose new industrial injury lands on top of a preexisting disability — but only through statutory doors that SB 171 rewrote effective July 13, 2026. The doors now read in whole person impairment, considered alone, after apportionment — numbers that come straight off the rating string. Enter them; this page checks every element.
What the numbers mean — and where they come from
Both doors are WPI “considered alone,” after apportionment — the impairment standing by itself, before the ×1.4 adjustment, occupation, and age steps, reduced by any apportionment to other causes. That is a number you read off the rating string, or compute in the free rating calculator. The 70% floor is the opposite: the combined permanent disability from all causes, preexisting included, after the full rating pipeline.
The evidence rule that decides these cases now
New §4754.1 locks proof of the preexisting disability to evidence in existence at the time of the subsequent injury — medical records, personnel files, prior awards. Retroactive prophylactic work restrictions written years later don’t count, med-legal reporting comes from the underlying claim’s evaluator, and a vocational expert’s report alone cannot establish the thresholds. If the paper trail didn’t exist on the date of injury, the door percentages above may be unreachable regardless of the medicine.
First hard SIBTF statute of limitations: 5 years from the date of the subsequent injury, or 6 months from resolution of the underlying PD claim — whichever is later — and the statute says §3202’s liberal-construction rule cannot extend it. The procedural rewrite applies to claims without a final determination as of July 13, 2026, but the deadline itself is carved out for claims already on file (§4757(b)). Anything you read about “a reasonable time” to file predates SB 171.
Meeting the thresholds is the beginning, not the end
Qualification opens the door; the benefit is then computed from the combined disability less what the employer owes for the subsequent injury alone, with §4753 offsets for other payments the worker receives. Payments must now begin within 30 days of a final determination. The full statutory walk-through — both doors, the evidence rule, the deadline, and what changed from the old law — is in the SIBTF guide; the July 2026 rewrite itself is covered in the news brief, cited to leginfo.
Statutory thresholds under Lab. Code §4751 as amended by SB 171 (Stats. 2026, ch. 83); verified against the enrolled text at leginfo.legislature.ca.gov. Threshold arithmetic only — whether a particular impairment, apportionment, or combination satisfies the statute is a legal and medical question. Not legal advice.
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