UV slope vs. M₁₆₀₀ for VANDELS galaxies selected in this work with σ_β ≤ 1 and at least three photometric bands available in the range 1230–2750 Å. Our data are color-coded according to three different redshift bins (2 <  z_bin1 <  3 <  z_bin2 <  4 <  z_bin3 <  5 in blue, dark red, and orange, respectively), with z estimated from VANDELS spectra. The median z in each bin is reported in the legend. For comparison, we show the M₁₆₀₀–β relations found by Hathi et al. (2016) at 2 <  z <  2.5 (empty gray circles), Bouwens et al. (2009) at ∼2.5 (cyan circles), Bouwens et al. (2014) at ∼4 (empty black circles), and Castellano et al. (2014) for LBGs at z ∼ 4 (empty black diamonds and light gray dashed best-fit line). The relation found by Pilo et al. (2019) for LBGs at z ∼ 3 is displayed as a light green dashed line.