Prime Minister Theresa May earlier today
The four drafts have been readied in an attempt to cover any eventuality when the 11 judges deliver their verdict on Tuesday.
It is understood that the various Acts of Parliament have been deliberately kept short so that Mrs May is given the power to trigger Article 50 as soon as possible.
The different drafts range from a “belt and braces” version that makes it explicit the UK is leaving more than a dozen European Union (EU) related bodies to one using the simplest wording possible.
However, the drafts will only be needed if the Supreme Court decides that MPs and peers must approve the start of Brexit talks before the government can trigger them.
Senior lawyers involved with the case will get to hear the verdict in private at 8am and are barred from communicating the the result to Mrs May until 9.15am, just 15 minutes before it made public.
It is widely believed that the government will lose the case.
An announcement regarding a new law in relation to Brexit is expected within hours of the court ruling.
The Secretary of State for Exiting the EU David Davis is due to address the House of Commons after the ruling and is expected to make the announcement if there is a defeat.
A government minister told said: “There are around four drafts. They all basically say the same thing – giving the government the power to affect withdrawal from the European Union.
Prime Minister Theresa May appearing on BBC 1's The Andrew Marr Show
“Even though the draftsmen have prepared drafts, we’re not regarding any of them as final until we know what the judgement says.
“We have no idea what the judges are going to say. The wording of the judgments is of extreme importance.”
Get Quotes on Home Insurance
Another minister said: “It was never going to be a magnums opus. It was always going to be a short, tight Bill."
Should the ruling go against the government it will face a tight deadline if it wants to meet Mrs May’s proposed desire to trigger Article 50 by the end of March this year.
Theresa May at PMQ's in the Commons earlier this week
Legislation would have to be passed by the Commons within a few days in order for it to pass to the Lords, giving it around one month to become law.
While there are signs of a rebellion from Labour backbenchers over Article 50 it would appear to be unlikely that the Conservative administration would be defeated in the Commons.
However the government could be given a severe headache if the Supreme Court rules that the various devolved administrations in Scotland, Wales and Northern Ireland must consider the implications of Brexit rather than just the Commons before talks can actually start with the EU.