The red and infrared intrinsic colours of B stars are derived from photometric observations through the UBV(R1)cJHK and H,8 filters of 257 early-type stars. Those stars for which the UBV and H,8 measurements match the published spectral class, and which show no other signs of peculiarity, are used to determine the intrinsic photometric colours of B stars in the red and infrared. From these intrinsic colours the interstellar reddening relationships for the red and infrared colours are evaluated, and the results are compared with previous estimates of these quantities. The values of R, E(B - V) and the distance are then determined for the individual stars. R is confirmed to be close to 3.1 in most cases, but was found to be much larger in some directions. The relationship between R and the location of a star in the Galaxy is investigated. Usually the abnormally reddened stars seemed to be associated with known regions of star formation. The paper also identifies seven likely variable stars and a number of stars with possible dust shells.