The full set of questions for the 2011 census - including new ones about citizenship and how well people can speak English - has been unveiled.
The 10-yearly survey of UK residents will take place on Sunday 27 March.
It will ask about the date overseas nationals entered the UK and the length of time they intend to stay.
Everyone in the UK on the day will be obliged to answer the questions, which also cover number of bedrooms and types of central heating in homes.
Those who do not complete the census risk being prosecuted.
Announcing the "major changes" in a written statement to MPs, Cabinet Office Minister Angela Smith said: "The questions have been devised to produce reliable and accurate data.
"The Office for National Statistics has carried out extensive consultations and testing over a number of years to ensure that the questions are justified, both in terms of the need for the information and public acceptability."
Ms Smith also announced that census forms would be delivered by post but could be completed online.
The government will also outsource the recruiting, training and payments to census staff as well as creating a central address register "to facilitate improved form delivery and field management".
Citizens will no longer be asked if they have access to a bath or shower but will be asked how many bedrooms their property has.
According to a specimen 2011 census on the Office for National Statistics website, they will also ask about "same sex civil partnership status" for the first time.
The specimen census asks "how would you describe your national identity?," offering English, Welsh, Scottish, Northern Irish, British or "other", with space to write in.
The section on ethnic groups has also been expanded from 2001, with separate categories for "Gypsy or Irish Traveller" and "Arab" for the first time.
It also asks: "How well can you speak English?... very well, well, not well or not at all."
The ONS is using the questions in the specimen census in a series of "rehearsals" but says it does not anticipate making major changes.
The questions to be included in the full census in 2011 will be put before Parliament in 2010.