The battle group has now been approved for combat for the next four years, the Slovenian Defence Ministry said on Friday afternoon.
The newspaper Večer reported in the morning that the group had passed the test this time, citing unofficial but reliable information.
The ministry confirmed that the test was conducted across five areas: preparations and planning, operations, logistics, communications and intelligence support, staff and administration.
"All segments were deemed combat ready. The battalion-sized battle group has thus met the Alliance's strictest standards of training used for forces at a high level of war combat readiness, and is ready and certified to engage in war combat in the next four years," the ministry said.
Defence Minister Andreja Katič expressed satisfaction with the outcome of the test and said she would comment on it after reading the evaluation report.
After the battle group failed the test in February, Katič dismissed Chief of the General Staff Major General Andrej Osterman and appointed his deputy Alan Geder in his place.
The failed test drew attention to the issues faced by the Slovenian military, above all understaffing and poor pay.
Geder has made steps to improve the situation somewhat and soldiers will see their pay increase by 19% on Sunday. Moreover, the battle group, which was understaffed in February, received additional soldiers.
The battalion-sized battle group was formed in March 2017. Specialising in 8-wheeled military vehicles, it consists of 820 permanent members. The group operates more than 200 combat and other military vehicles.