Here is the deal with safe harbor 401(k) plans: employers adopt them primarily so they don't have to perform non-discrimination testing. In exchange, employers promise to match employee elective deferrals (in amounts that meet the statute requirements) and agree to fully vest them.
So, there are SEVERAL different issues going on here:
1. By when do employers have to contribute employee deferrals (taken from employee wages) to the plan, and allocate them to each participant's account?
Plan Assets. The frequency with which participants can make elective deferral contributions to the plan is usually spelled out in the plan or SPD (Summary Plan Description). It usually corresponds with payroll runs. However, once the employer reduces employee wages to direct those amounts to be allocated to each participant's account in the trust and invested in accordance with their investment instructions, the transaction must be completed within a reasonable period of time. The late payment plan errors usually apply here. You may see language about plan assets not being timely contributed to the plan and lost earnings resulting from a delay in putting funds to work after being invested. There are lots of correction applications on this issue through EPCRS.
Types of Contributions. Not all plans have the same provisions, so this may not apply to your facts and circumstances, but you said you were still waiting on employer contributions for 2015. This makes me wonder as to which specific contribution you're waiting for. Is it your elective deferral contributions from 2015? Is it the matching contributions on the elective deferral contributions from 2015? Are there other types of contributions the plan authorizes that you haven't received yet?
Eligibility for Contributions. You mentioned this issue is with your former employer's plan. I presume that means you have separated from service with your employer, is that correct? If so, it is possible that you did not satisfy all of the requirements for receiving an employer contribution. For example, participants who are not employed on the last day of the plan year or those who've left employment due to retirement or disability. Again, you'll need to read the SPD. It should describe any provisions that limit your eligibility for a matching contribution.
2. By when does the employer have to contribute the amount of any employer matching (or other type) contributions. These contributions generally are contributed to the plan, then allocated each participant's share to his or her accounts, in accordance with the terms of the plan. This could be at the same time as elective deferrals, it could be monthly, quarterly, etc. HOWEVER, the employer has until the later of: 1. The end of the plan year (December 31 for a calendar year plan year); or 2. The employer's deadline for filing it's tax return, plus extensions, to make the employer contribution for the prior year.
These might be helpful:
Code section 404(a)(3):
https://www.law.cornell.edu/uscode/text/26/404Treas. regs. 1.404(a)-1
Publication:
https://www.irs.gov/pub/irs-tege/epche903.pdfI really recommend that you make an appointment with HR, or whomever else has responsibility for the plan, and ask them to explain how your contributions (employee and employer) were calculated and tell you when amounts were contributed or will be. Good luck!
