The same-sex marriage survey has exposed sharp differences in attitudes between Sydney's east and west after more than 1.1 million voters across the city voted against any change to marriage laws.
Sydney had three of the five highest yes-voting electorates in the nation (including equal top), as well as the seven electorates with the highest no votes.
Overall, 17 of Greater Sydney's 29 federal electorates returned a majority yes vote, while 12 had a majority of no voters. The city-wide yes vote - 55.29 per cent - was more than 6 percentage points below the national figure and 10 percentage points lower than Melbourne.
The wealthy eastern region of the city responded with a resounding yes. The inner-city electorate of Sydney had a vote of 83.7 per cent - the equal highest in Australia (with the electorate of Melbourne).
Prime Minister Malcolm Turnbull's seat of Wentworth was next highest with 80.8 per cent followed by the inner west's Grayndler with 79.9 per cent.
In former prime minister Tony Abbott's electorate of Warringah the yes vote was a crushing 75 per cent - the 10th highest of Australia's 150 federal electorates.
But a swath of western Sydney electorates voted for the status quo.
The electorate with the highest no vote in the nation - 73.9 per cent - was the Labor-held seat of Blaxland, which takes in the suburbs of Bankstown, Yagoona and Auburn.
The electorate of Watson, which takes in Lakemba, Greenacre and Campsie, was not far behind with a no vote of 69.9 per cent.
The western Sydney seat of McMahon, held by shadow treasurer Chris Bowen, had Australia's third highest no vote at 64.9 per cent.
The survey results showed 1.1 million Sydneysiders voted no while 1.37 million voted yes.
Demographic factors help explain the sharp differences across the city.
Census data shows that electorates with a majority of no voters also have a large share of the population with a religious affiliation.
In the electorate of Blaxland, for example, just 14 per cent of the population opted for "no religion" in last year's census.
There was a similar low "no religion" share in the seats of Werriwa, McMahon, Fowler and Watson, which all returned a strong no vote in the marriage survey.
The 2016 census showed 29 per cent of the population of the Blaxland electorate identified with Islam, 36 per cent with Christianity and 8 per cent with Buddhism.
Electorates with a strong majority of no voters also tended to have a significant share of the population born in non-English speaking countries.
There was a narrow majority of no voters (50.9 per cent) in the north-western Sydney electorate of Mitchell, which has a relatively large share of Christians and is home to the Hillsong mega-church.
However, in the southern suburban electorates of Cook and Hughes, which both have a high proportion of residents affiliated with Christianity, yes voters were in a majority.
The "blue ribbon" north shore electorates of Mackellar, Bradfield, North Sydney and Warringah all had a strong yes majority.
The yes vote also prevailed in the so called "Howard Battler" outer-western Sydney electorates of Lindsay, Macquarie and Macarthur.
In the seat of Bennelong - where a byelection has been called following the resignation of Liberal MP John Alexander over his citizenship status - the result was line-ball with a no vote of 50.2 per cent.
The yes vote among NSW voters outside Sydney was significantly higher than in the capital at 61.5 per cent. Also, every NSW federal electorate beyond the Sydney basin had a majority of yes voters.
