Insured persons can close gaps in the occupational pension plan by making additional contributions and receive higher benefits in accordance with the pension fund regulations. The possible purchase is determined by the pension fund regulations and is based on the maximum regulatory benefits. These are determined by a fictitious extrapolation that calculates the theoretical retirement capital based on the current salary since the start of the savings process within the pension fund. The difference between this theoretical retirement capital and the capital actually available is referred to as the purchase gap and can be closed by voluntary contributions. Voluntary contributions to the pension fund can be deducted from taxable income. Due to the tax progression, it may be advisable to spread the contributions over several years instead of making the maximum contribution at once.