Colonial Spanish sources, chiefly Bernardino de Sahagun's Florentine Codex, preserve the tonalpohualli in unusual detail precisely because Spanish missionaries considered it dangerous: the calendar was inseparable from the divinatory priesthood's authority, and understanding it was necessary to suppress it, so the very effort to eradicate the system is what left the fullest record of how it worked. The state sponsored priesthood that read the tonalamatl for the Aztec elite did not survive the conquest, and daily divinatory practice by trained tonalpouhque working from painted books ended with it.
The cycle's structure has not disappeared from Indigenous Mesoamerican life, though. Variants of the two hundred sixty day count are still kept by Maya daykeepers in Guatemala under the related name tzolkin, and among Nahua communities and Mexica revivalist movements the tonalpohualli itself has been reconstructed for personal and ceremonial use, most visibly as a source of individual day sign identity rather than as a state instrument of divination. The reconstructed modern practice is not a seamless continuation of the pre-conquest priesthood's calendar. It draws on the same colonial sources that preserved the system in order to recover a use for the calendar that Spanish suppression had broken.