Constance Hopkins Snow Dallas (April 28, 1902 – January 13, 1983) was an American politician. A member of the Democratic Party, she served on the Philadelphia City Council as a representative of the city's 8th district. Born in New York and educated in Europe, Dallas came to Philadelphia as a teenager. After marriage and raising children, she entered local politics as a reform-minded Democrat. Following an unsuccessful run for City Council in 1947, she was elected in 1951, the first woman to serve in that legislative body.
Dallas was elected as part of a coalition between the Democratic Party organization and reforming independents who wished to challenge the Republican city government. The reforms in question focused many on shifting power from the city council to the mayor and in converting the longstanding patronage system to convert to a merit system of city employment. Her reformist tendencies clashed with some of the party organization, and she went down to defeat in 1955. After a second career as a newspaper editor and investment banker, she retired in 1978 and died in 1983.