The incident on Friday occurred two days before France officially marked the end of its military operations in the West African nation, where in 2015 some 400 French special forces had been sent to help fight an insurgency that spread from neighbouring Mali.
The soldiers were ambushed in Oudalan province, in Burkina Faso's Sahel region, which shares a border with Mali.
The provisional death toll was revised up from eight reported earlier on Monday after an additional 43 bodies were found, the army said.
It did not directly blame anyone for the attack but said around 160 "terrorists" were killed in a counter-offensive air strike, up from about 60 in the previous statement.
Burkina Faso is one of several West African countries grappling with a jihadist insurgency that took root in Mali after a Tuareg rebellion in 2012.
Violence has spread to neighbouring countries and beyond despite costly international military interventions and United Nations peacekeeping efforts. Thousands have been killed and millions displaced across the Sahel region south of the Sahara.
Frustrations over the lack of safety spurred two coups in Mali and two in Burkina Faso since 2020, placing power in the hands of juntas that have been burning bridges with traditional Western allies.
France's relations with Burkina Faso have sharply deteriorated over the past year, culminating with Ouagadougou giving its former coloniser one month to withdraw troops in January.
France withdrew its forces from Mali last year after the junta there started working with Russian military contractors. Several other countries have since followed suit.
The withdrawals have increased concerns about the outlook for a conflict that has seen the number of Islamist attacks more than double since 2020, according to the Africa Center for Strategic Studies.
Medical charity Medecins Sans Frontieres suspended its operations in Burkina Faso last week to carry out a risk assessment following the killing of two its staff on February 8.Â
