AbstractThe rise of HIV‐1 drug resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs) threatens the long‐term success of NNRTI‐based therapies. Our study aims to describe the circulation of major resistance‐associated mutations (RAMs) for NNRTIs in people living with HIV (PLWH) in Italy from 2000 to 2020. We included 5982 naïves and 28 505 genotypes from 9387 treatment‐experienced PLWH from the Antiviral Response Cohort Analysis (ARCA) cohort. Transmitted drug resistance (TDR) was found in 12.5% and declined from 17.3% in 2000–2003 to 10.9% in 2016–2020 (p = 0.003). Predictors of TDR were viral subtype B [vs. non‐B, adjusted odds ratio (aOR) = 1.94, p < 0.001], zenith viral load (VL) (per 1 log₁₀ higher, aOR = 0.86, p = 0.013), nadir CD4 cell count (per 100 cells/μL increase aOR = 0.95, p = 0.013). At least one RAM for NNRTIs among treatment experienced PLWH was detected in 33.2% and pre‐treatment drug resistance (PDR) declined from 43.4% in 2000–2003 to 20.9% in 2016–2020 (p < 0.001). Predictors of PDR were sexual transmission route (vs. others, aOR = 0.78, p < 0.001), time since HIV diagnosis (per 1 month longer, aOR = 1.002, p < 0.001), viral subtype B (vs. non B, aOR = 1.37, p < 0.001), VL (per 1 log₁₀ higher, aOR = 1.12, p < 0.001), nadir CD4 count (per 100 cells/μL increase, aOR = 0.91, p < 0.001), previous exposure to any NNRTI (aOR = 2.31, p < 0.001) and a more recent calendar year sequence (any time span > 2008 vs. 2000–2003, any aOR <1, p < 0.001). Circulation of RAMs to NNRTIs declined during the last 20 years in Italy. NNRTIs remain pivotal drugs for the management of HIV‐1 due to safety concerns and long‐acting options.