Montana Impairment Rating Guide
Montana workers' compensation uses the 6th Edition of the AMA Guides to the Evaluation of Permanent Impairment under MCA § 39-71-711.
Which Edition?
AMA Guides Edition 6th Edition
Statutory Authority
MCA § 39-71-711
PPD Calculation
Statutory Maximum Weeks 375 weeks
PPD weeks = WPI% × 375 weeks (plus statutory multipliers for age, education, and wage at injury).
Notes
AMA Guides 6th Edition specified by statute for injuries on/after July 1, 2011.
Frequently Asked Questions
Which edition of the AMA Guides does Montana use?
Montana uses the 6th Edition of the AMA Guides to the Evaluation of Permanent Impairment under MCA § 39-71-711. The applicable edition is generally determined by the worker's date of injury; consult counsel for cases that straddle effective-date transitions.
How is permanent partial disability calculated in Montana?
PPD weeks = WPI% × 375 weeks (plus statutory multipliers for age, education, and wage at injury).
Where can I find a certified impairment rater in Montana?
Browse our directory of certified impairment raters listed for Montana. View the directory →
Does this information constitute legal or medical advice?
No. This page provides general statutory and methodological information for educational purposes only. Statutes change, case law shifts controlling interpretation, and individual cases turn on facts beyond what reference material can capture. Consult qualified legal counsel and a credentialed rating physician for any specific matter.
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