RTB may refer to:
Businesses and organizations Reasons to Believe, a creationist group Residential Tenancies Board of Ireland; see State Agencies of the Republic of Ireland Richard Thomas and Baldwins, a former British steelmaker
Broadcasters RTBF, Belgium Radio Television of Belgrade, Yugoslavia Radio Television Brunei Radio Télévision du Burkina, Burkina Faso
Other uses Juan Manuel Gálvez International Airport (IATA airport code), Roatán, Honduras Real-time bidding, in online advertising Right to Buy, a policy of the United Kingdom government allowing some tenants to purchase their home Rouge the Bat, a character from the Sonic the Hedgehog franchise