Basalt textile reinforced mortar (BTRM) has drawn attention as an innovative retrofitting composite, due to its superior characteristics including simplicity in application, high performance in addition to low cost, in comparison to FRP. Unreinforced masonry (URM) buildings constitute a large portion of current worldwide buildings which suffer lack of resistance to wind and seismic loading. Thus, BTRM represents an ideal technique for out of plane retrofitting for URM walls. This study aims to investigate the out of plane behavior of URM walls retrofitted by using BTRM. A Group of five URM wall specimens were constructed in vertical spanning scheme. Another group of five specimens were constructed in horizontal spanning scheme. Parameters under study for both groups include mesh opening size (5 × 5 mm and 10 × 10 mm), number of reinforcing layers (two and four layers) and retrofitting scheme (one side or both sides). The efficiency of BTRM has been demonstrated through the investigation results. Out of plane flexural capacity remarkably increased by 188% to 400% comparatively to control samples. In addition, energy absorption increased 22 to 66 times. An ACI model has been modified to be more reliable for flexural capacity prediction retrofitted URM walls.