Company: SFNC
Filing Date: 2025-09-10
Form Type: 424B5
Source: 0001193125-25-200113
Chunk: 37

Company: SIMMONS FIRST NATIONAL CORP
Filing Date: 2025-09-10
Form: 424B5
Chunk 37
---
 rate shall be deemed to be zero.

For the purpose of calculating the interest on the Notes for each interest period during the floating rate period when the Benchmark is
Three-Month Term SOFR, “Three-Month Term SOFR” means Term SOFR for a tenor of three months that is published by the Term SOFR Administrator at the Reference Time for any floating rate interest period, as determined by the calculation
agent after giving effect to the Three-Month Term SOFR Conventions. See “Calculation Agent.”

S-24

The following definitions apply to the foregoing definition of Three-Month Term SOFR:

“Benchmark” means, initially, Three-Month Term SOFR; provided that, if the calculation agent determines on or prior to the
Reference Time for any floating rate interest period that a Benchmark Transition Event and its related Benchmark Replacement Date have occurred with respect to Three-Month Term SOFR or the then-current Benchmark, then “Benchmark” means
the applicable Benchmark Replacement for such floating rate interest period and any subsequent floating rate interest periods.

“Corresponding Tenor” means (i) with respect to Term SOFR, three months, and (ii) with respect to a Benchmark
Replacement, a tenor (including overnight) having approximately the same length (disregarding business day adjustment) as the applicable tenor for the then-current Benchmark.

“Federal Reserve Bank of New York’s Website” means the website of the Federal Reserve Bank of New York (the
“FRBNY”) at http://www.newyorkfed.org, or any successor source. The foregoing Internet website is an inactive textual reference only, meaning that the information contained on the website is not part of this prospectus supplement
or the accompanying prospectus or incorporated by reference herein or therein.

“Reference Time” with respect to any
determination of the Benchmark means (i) if the Benchmark is Three-Month Term SOFR, the time determined by the calculation agent after giving effect to the Three-Month Term SOFR Conventions, and (ii) if the Benchmark is not Three-Month
Term SOFR, the time determined by the calculation agent after giving effect to the Benchmark Replacement Conforming Changes.

“Relevant Governmental Body” means the Federal Reserve and/or the FRBNY, or a committee officially endorsed or convened by the
Federal Reserve and/or the FRBNY or any successor thereto.

“SOFR” means the secured overnight financing rate published by the
FRBNY, as the administrator of the