L-error estimates for B-spline Galerkin finite element solution of the Rosenau-Burgers equation are considered. The semidiscrete B-spline Galerkin scheme is studied using appropriate projections. For fully discrete B-spline Galerkin scheme, we consider the Crank-Nicolson method and analyze the corresponding error estimates in time. Numerical experiments are given to demonstrate validity and order of accuracy of the proposed method. (c) 2015 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 877-895, 2016