US · guidance
CMS Pub. 100-04, ch. 4, § 20.6.3
Modifiers -LT and -RT
LT: Left side (used to identify procedures performed on the left side of the body)
RT: Right side (used to identify procedures performed on the right side of the
body)
Modifiers LT and RT apply to codes that identify procedures that can be performed on
paired organs, e.g., ears, eyes, nostrils, kidneys, lungs, and ovaries.
These modifiers should be used whenever a procedure is performed on only one side.
Hospitals should report the appropriate RT or LT modifier to identify which of the paired
organs was operated upon. Do not report modifiers RT and LT when modifier 50 applies.
History
(Rev. 11937; Issued: 03-31-23; Effective: 04-01-23; Implementation: 04-03-23)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
a7f7e230f90c8130365cdc0a7e7a4741f8f8f4737328f29ff07f052eb496b644
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