Quantifying induced virion production from single proviruses is important for assessing the effects of HIV-1 latency reversal agents. Limiting dilution ex vivo cultures of resting CD4⁺ T cells from 14 HIV-positive volunteers revealed that virion production after T-cell activation from individual proviruses varies by 10,000-fold to 100,000-fold. High-producing proviruses were associated with increases in cell-associated HIV-1 DNA levels, suggesting that reactivated proviruses proliferate. Single-cell analyses are needed to investigate differences in proviral expansion and virus production following latency reversal.