In the title salt (2S,4S,8R)-1-butyl-2-[(R)-(hydr-oxy)(6-methoxy-quinolin-4-yl)meth-yl]-8-vinyl-quinuclidin-1-ium tetra-fluoro-borate, C(24)H(33)N(2)O(2) (+)·BF(4) (-), the butyl substituent at the 1-position is in an equatorial conformation with respect to the unsubstituted six-membered ring and the four butyl C atoms are almost coplanar with the ring N and vinyl C atoms (r.m.s. deviation = 0.046 Å). In the crystal, the cations are linked by O-H⋯N hydrogen bonds. The F atoms of the tetra-fluoro-borate group are disordered over two sets of site with an occupancy raitio of 0.552 (8):0.448 (8).