Safe harbor matching contributions. Safe harbor 401(k) plans are the most popular type of 401(k) plan used by small businesses today. They automatically pass annual ADP/ACP and top heavy tests and allow business owners to make salary deferrals up to the legal limit ($18,500 + $6,000 catch-up for 2018) without the risk of corrective refunds or contributions.
https://www.employeefiduciary.com/blog/401k-matching-contributions