Interest rates: underpayment and overpayments. The rates for interest determined under section 6621 of the code for the calendar quarter beginning January 1, 2015, will be 3 percent for overpayments (2 percent in the case of a corporation), 3 percent for the underpayments, and 5 percent for large corporation underpayments. The rate of interest paid on the portion of a corporation overpayment exceeding $10,000 will be 0.5 percent.

2014 Base Period T-Bill Rate. The table of interest factors that Rev. Rul. 2014–27 provided for compounding the “base period T-bill rate” under section 995(f) of the Internal Revenue Code is replaced by the table in this revenue ruling. Rev. Rul. 2014–27 modified.

2015 covered compensation tables; permitted disparity. The covered compensation tables under section 401 of the Code for the year 2015 are provided for use in determining contributions to defined benefit plans and permitted disparity.

This announcement extends to June 30, 2015, the deadline for submitting on-cycle applications for opinion and advisory letters for pre-approved defined benefit plans for the plans’ second six-year remedial amendment cycle. This announcement also provides a two day extension (from Saturday, January 31, 2015, to Monday, February 2, 2015) for Cycle D on-cycle submissions (primarily individually designed plans including multiemployer plans).

This notice contains the 2014 Cumulative List of Changes in Plan Qualification Requirements (2014 Cumulative List) described in section 4 of Rev. Proc. 2007–44, 2007–2 C.B. 54. The 2014 Cumulative List is to be used by plan sponsors and practitioners submitting determination letter applications for plans during the period beginning February 1, 2015 and ending January 31, 2016.