Ind. Code § 22-4-10-5
Any employer may make voluntary payments in addition to the contributions required under this article, and the same shall be credited to its experience account. Such voluntary contributions shall not be used in the computation of reduced rates unless such contributions are paid prior to the expiration of one hundred twenty (120) days after the beginning of the year for which such rates are effective. Such payments shall be included in the experience account as of the computation date only if they are made within thirty (30) days following the date upon which the department mails notice that such payments may be made with respect to a calendar year. Such voluntary payments when accepted from an employer will not be refunded in whole or in part.
Formerly: Acts 1947, c.208, s.1006; Acts 1951, c.295, s.8. As amended by P.L.144-1986, SEC.100; P.L.18-1987, SEC.35.