As most HIV rapid tests (HRT) detect only HIV‐1/2 antibodies, their performance during primary HIV infection is poor. Determine HIV Early detect (Abbott) (Determine) is the only HRT with an HIV‐1 p24‐antigen detection, but the impact of this addition in shortening the diagnostic window remains unclear. A total of 183 HIV‐1 primary infection samples were tested using the HRTs Determine and ONE STEP anti‐HIV (1&2) Test (InTec Products) (One‐Step). The pre‐seroconversion subgroup was defined as p24‐antigen positivity without Western blot nor Liaison XL (fouth generation enzyme immunoassay with distinct signal for p24‐antigen and HIV‐1 antibody) HIV‐1 antibodies. Global sensitivity (95% CI) was 95% (91–97) for Determine versus 80% (74%–85%) for One‐Step (difference p = 1.38e−06). Pre‐seroconversion subgroup sensitivity was lower, at 71.9 (54.6%‐84.4%) for Determine and 9.7% (3.3%–24.9%) for One‐Step. Among the 45 samples with an HIV‐1 infection date, no HRT was reactive up to 2 weeks. Between 2 and 3 weeks, Determine sensitivity was 78% (45%–95%) versus 56% (27%–81%) for One‐Step. From 3 weeks to 1 month Determine sensitivity was 90% (62%–98%) and One‐Step 45% (21%–72%). The last negative sample occurred at 3 weeks for Determine versus 70–90 days for One‐Step. HRT with p24‐antigen detection significantly shortens the diagnostic window from approximatively 3 months to 1 month. HRTs should be used with caution in the first month after HIV infection.