When the regiment was raised it carried two colours from the two disbanded regiments Jönköping Regiment and Kalmar Regiment. A new regimental colour was presented to the Northern Småland Regiment (I 12) in Eksjö by His Majesty the King Gustaf VI Adolf on 11 September 1954 which replaced the two older ones. It was used as regimental colour by I 12 until 1 July 2000. The colour is drawn by Brita Grep and embroidered by hand in insertion technique probably by the company Libraria. The battle honours from the two previous regiments were now added to the new colour. Blazon: "On a quarterly cloth on the first and fourth bays the provincial badge of Småland; on yellow a red lion rampant, armed blue, in the forepaws a red crossbow with white arrowhead and black bow, string and trigger (a legacy from the former Kalmar Regiment, I 21), on the second and third bays the town badge of Jönköping; on red, from a blue wavy base a tripletowered white castle embattled issuant, windows and gates black and a hoisted white gate grill (a legacy from the former Jönköping Regiment, I 12). On a red border at the upper side of the colour, battle honours (Lützen 1632, Wittstock 1636, Warsaw 1656, Landskrona 1677, Klisow 1702, Malatitze 1708, Hälsingborg 1710 in yellow."