<prompt> Human: My employer matches 401k contributions yearly instead of quarterly like many companies do. I am trying to find the equation that would allow me to calculate the difference between yearly and quarterly matching over a certain number of years assuming an 8-10 average yearly return.  <response>: Your company likely does this because they end up contributing less to do it annually than quarterly. At a prior job, I audited 401k plans - most with an annual employer contribution had requirements that a participant had to be employed there for the entire year or at year-end to be eligible for the employer contribution. Its something they could use to get people to stay with the company longer. 