We have a Sarsep plan in our company. We have a employee who is 52 years old and making 60k year. Per the contribution limits he can contribute to 25% of his income(15k) or 15,500 whichever is lower. Therefore he can contribute 15k. Now my question is since he is over 50 can he contribute 20,000(15k+5k) or is he limited to 15k(25% limit). Thanks

Yes. He can defer $20,000. Remember, the catchup does not count against the 415 limit; while it does remain at 25% of SEPs (SARSEPS). You should ensure the other rules are followed as well.