A SEP has a plan year end of 4/30/07. When are contributions due.

We have been asked to design a 401(k) plan for this group and they want to make their final SEP contribution.

According to IRS pub 560 P 7, SEP contributions are not made on a plan yr basis. They are deducted for a calendar yr which ends with or within the employer's tax yr or for the fiscal yr of the employer. Contributions must be made by the date for filing the employer's tax return with 6 month extension. When does the employer tax yr end?

I think the publication is saying you MAY maintain a SEP on a calendar year basis if you are a fiscal year taxpayer. The more likely scenario, IMO, is that it's maintained on the same (fiscal) year as the business and therefore contributions would be due July 15 unless extended to Dec 15.

I believe the deciding factor is what SEP document you are using. The model 5305-SEP must be maintained on a calendar year basis. A non-model SEP could presumably be maintained on a fiscal year basis that is other than calendar year. I've seen a lot of fiscal year taxpayers who nevertheless use the model SEP.