The annual defined contribution limit is the maximum amount that can be added to a retirement account in a single year. This includes contributions from both the employee and the employer. It applies to plans like a Solo 401k or SEP IRA. The goal of this limit is to make sure retirement savings stay fair and within set boundaries. Even if you contribute to more than one plan, your combined total generally cannot go over this limit. The IRS sets this number and updates it from time to time to reflect changes in the economy. Knowing this limit helps you plan how much you can save each year for retirement.