The Romance counting system is numerical – with residues of earlier systems whereby each commodity had its own unit of quantification – and decimal. Numeral formations beyond ‘10’ are compounds, combining two or more numerals that are in an arithmetical relation, typically that of addition and multiplication. Formal variation across the (standard) Romance languages and dialects and across historical stages involves the relative sequence of the composing elements, absence or presence of connectors, their synthetic vs. analytic nature, and the degree of grammatical marking. A number of ‘deviant’ numeral formations raise the question of borrowing vs independent development, such as vigesimals (featuring a base ‘20’ instead ‘10’) in certain Romance varieties and the teen and decad formations in Romanian. The other types of numeral in Romance, which derive from the unmarked and consistent cardinals, feature a significantly higher degree of formal complexity and variation involving Latin formants and tend toward analyticity. While Latin features prominently in the Romance counting system as a source of numeral formations and suffixes, it is only in Romance that the inherited decimal system reached its full potential, illustrating its increasing prominence, reflected not only in numerals, but also in language acquisition, sign language, and post-Revolution measuring systems.