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The reaction in phase-transfer catalyzed conditions of 3(5)-methyl-1<i>H</i>-pyrazole with chloroform affords four isomers <b>333</b>, <b>335</b>, <b>355</b> and <b>555</b> in proportions corresponding to the polynomial expansion (a + b)³, with a = 0.6 and b = 0.4, a and b being 3-methyl and 5-methyl proportions. The up (<i>u</i>) and down (<i>d</i>) conformation of the pyrazolyl rings with regard to the Csp³&#8315;H atom was established by X-ray crystallography and by ¹H-, ¹³C- and ¹⁵N-NMR in solution combined with gauge-including atomic orbitals (GIAO)/B3LYP/6-311++G(d,p) calculations. A comparison with other X-ray structures of tris-pyrazolylmethanes was carried out.