The Unidad Reguladora de Servicios de Comunicaciones (URSEC), Montevideo announced a change in Uruguay’s telephone numbering plan starting August 29, 2010.
The change: all fixed telephone numbers consisting of 7 digits were added digit 4 in the beginning. Numbers in Montevideo and Maldonado departments were not affected since they had been 8 digit for quite awhile (2 ??? ???? and 4 2?? ???? respectively). Cellular numbers are also not affected by this change.
Changes in the way Uruguayans dial telephone numbers nationally
To dial any Uruguay landline from Uruguay one has to use the complete 8 digit phone number. Adding the initial zero before landline numbers is no longer necessary. Mobile phone numbers will still be dialed using the initial zero (09xxx xxxx).
To conclude, all fixed and mobile telephone numbers in Uruguay are now 8 digit.
The page below has
complete info on dialing to Uruguay