Publication 560
taxmap/pubs/p560-014.htm#en_us_publink10008959In general, if your plan is a money purchase pension plan or
a defined benefit plan, you must actually pay enough into the plan to satisfy
the minimum funding standard for each year. Determining the amount needed to
satisfy the minimum funding standard for a defined benefit plan is complicated,
and you should seek professional help in order to meet these contribution
requirements. The amount is based on what should be contributed under the plan
formula using actuarial assumptions and formulas. For information on this
funding requirement, see section 412 and its regulations.
taxmap/pubs/p560-014.htm#en_us_publink10008960If your plan is a defined benefit plan subject to the minimum
funding requirements, you must make quarterly installment payments of the
required contributions. If you do not pay the full installments timely, you may
have to pay interest on any underpayment for the period of the underpayment.
taxmap/pubs/p560-014.htm#en_us_publink10008961The due dates for the installments are 15 days after the end
of each quarter. For a calendar-year plan, the installments are due April 15,
July 15, October 15, and January 15 (of the following year).
taxmap/pubs/p560-014.htm#en_us_publink10008962Each quarterly installment must be 25% of the required annual
payment.
taxmap/pubs/p560-014.htm#en_us_publink10008963Additional contributions required to satisfy the minimum funding
requirement for a plan year will be considered timely if made by 81/2 months after the end of that year.