The observation of latent light-assisted poling (LAP) in lithium niobáte single crystals is reported. More specifically, the nucleation field is reduced and remains reduced for an extended time period (up to several hours) after irradiation with ultrafast (-150 fs) laser light at a wavelength of 400 nm. The maximum nucleation field reduction measured using latentLAP (62%) was significantly higher in comparison with regular non-timedelayed LAP (41%) under identical irradiation conditions in undoped congruent lithium niobáte crystals. No latent-LAP effect was observed in MgO-doped crystals for the experimental conditions used, despite the strong effect observed using regular LAP. The latent-LAP effect is attributed to the formation of a slowly decaying photo-induced spacecharge distribution which assists local ferroelectric domain nucleation. The dynamics of latent-LAP are compared with the dynamics of photorefractive grating decay, recorded in lithium niobáte crystals of different doping, confirming the space charge hypothesis.