Ark. Code Ann. § 3-7-109

On the failure of any person, liable therefor, to pay the taxes imposed by §§ 3-7-101 — 3-7-104 and 3-7-106 — 3-7-110 within fifteen (15) days after the taxes have become due, he or she shall be deemed delinquent. A penalty of twenty percent (20%) on the amount of license tax due shall attach. The Auditor of State shall at once cause proceedings to be instituted for the collection of the license tax, with such interest and penalties as may be provided by law for the collection of other taxes.