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In this paper, the microwave (MW)-assisted catalyst-free and mostly solvent-free Kabachnik&#8722;Fields reaction of amino alcohols, paraformaldehyde, and various &gt;P(O)H reagents (dialkyl phosphites, ethyl phenyl-<i>H</i>-phosphinate, and secondary phosphine oxides) is reported. The synthesis of <i>N</i>-2-hydroxyethyl-&#945;-aminophosphonate derivatives was optimized in respect of the temperature, the reaction time, and the molar ratio of the starting materials. A few by-products were also identified. <i>N</i>,<i>N</i>-Bis(phosphinoylmethyl)amines containing a hydroxyethyl group were also prepared by the double Kabachnik&#8722;Fields reaction of ethanolamine with an excess of paraformaldehyde and secondary phosphine oxides. The crystal structure of a 2-hydroxyethyl-&#945;-aminophosphine oxide and a bis(phosphinoylmethyl)ethanolamine was studied by X-ray analysis.