In this work, the crack tip fields in the neighborhood of a stationary mode I crack in a hardening Cu single crystal, under tensile load was investigated. A modified boundary layer (MBL) simulation was performed with the implementation of Bassani and Wu (1991) hardening model while taking into account the crystal elastic anisotropy. The effect of latent hardening ratio (LHR) on the stress and strain fields was studied by considering three different values of LHR, q, viz. diagonal hardening (q=0) and latent hardening (q=1,1.4). In addition, the effect of crack tip constraint representing different test specimens and load conditions was examined with the inclusion of T-stress through the imposed displacement boundary condition. Important observations from this work include the suppression of kink band, presence of elastic sectors, and the occurrence of triple slip near the crack tip. The increase of T-stress suppressed the plastic strain accumulation and showed a decrease in the number of triple slip sectors near the crack tip. Whereas, the increase in q made the triple slip regions slightly prominent with wider angular spread for non-negative T. But, for negative T case, rise in q caused a suppression in the angular spread of triple slip regions. Also, the implementation of T-stress allowed for a correlation between full 3D and 2D plane strain simulations in the analysis of crack tip fields for hardening single crystals. The present study offers a comprehensive investigation of the effect of crack tip constraint and latent hardening ratio on the crack tip fields for hardening FCC single crystals.