NCCI edits for G0421
Code page: https://localishealth.com/hcpcs/G0421
NCCI release: 2026 D
Source: https://www.cms.gov/medicare/coding-billing/national-correct-coding-initiative-ncci-edits

NOT SEPARATELY PAYABLE TOGETHER—NO NCCI-ASSOCIATED MODIFIER BYPASSES THE EDIT (modifier indicator 0)
36591    G0421 is Column One, 36591 is Column Two—36591 denies
36592    G0421 is Column One, 36592 is Column Two—36592 denies
96523    G0421 is Column One, 96523 is Column Two—96523 denies
99452    G0421 is Column One, 99452 is Column Two—99452 denies

BILLABLE TOGETHER ONLY WHEN AN NCCI-ASSOCIATED MODIFIER IS APPROPRIATE (modifier indicator 1)
G0420    G0420 is Column One, G0421 is Column Two—G0421 denies

MUE units per patient per date of service: 2