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We report efficient non-resonant ground state excitation at 1064 nm of trivalent neodymium (Nd 3+ ) ions in stoichiometric neodymium aluminum borate NdAl 3 (BO 3 ) 4 nanoparticles, which are crystalline and, besides the large content of Nd 3+ ions, present excellent photoluminescence properties. Up-conversions (UCs) were observed and the energy pathways identified, as starting by multi-phonon assisted ground state absorption ( 4 I 9/2 → 4 F 3/2 ) and excited state absorption ( 4 I 11/2 → 4 F 3/2 ) with the population of the 4 I 11/2 level by thermal coupling with the ground state. The excited state 4 I 11/2 is also populated by relaxations of the Nd 3+ increasing the population of the 4 F 3/2 level. Cross-relaxation among two Nd 3+ ions ( 4 F 3/2 , 4 I 9/2 )→( 4 I 15/2 , 4 I 15/2 ) with subsequent phonon emission leads to two ions at the 4 I 11/2 level every iteration triggering a photon avalanche mechanism which greatly enhances the efficiency of the UCs. Ladder thermal excitation 4 F 3/2 →[ 4 F 5/2 , 2 H 9/2 ]→[ 4 F 7/2 , 4 S 3/2 ]→ 4 F 9/2 was achieved, and the ground state relaxation from these levels provided emission at 880 nm, 810 nm, 750 nm, and 690 nm, respectively. Energy transfer UCs (Auger) between Nd 3+ ions at the 4 F 3/2 level allowed population of the [ 2 G 3/2 , 4 G 7/2 ] from which relaxations to the 4 I 9/2 , 4 I 11/2 , and 4 I 13/2 states provided emissions around 536 nm, 600 nm, and 660 nm, respectively. Associated to the nonradiative relaxations, we observed the heating of the nanoparticles (22 °C to 240 °C) with subsequent thermal enhancement of the frequency UCs due to the redistribution of population among coupled energy levels of the Nd 3+ ions. The present results have potential applications in super-resolution imaging and nanothermometry.