Safe Harbor Nonelective retroactive to Jan 1

[AKconsult]

I have a client with a brand new plan. The plan is effective retroactive to 1/1/08, with 401(k) provision effective 2/15/08. Plan is using safe harbor nonelective. Can the nonelective contribution be calculated on pay from 1/1/08 - 12/31/08 or can I only use pay from 2/15/08? I am getting various answers from attorneys with whom I have posed this question...

[Kimberly S]

How does the plan define compensation? If it uses full year compensation for contribution calculation purposes the answer may be different than if it uses compensation while a participant.