The "Yes" and "No" camps mobilised thousands of volunteers to hand out leaflets and hold rallies across Scotland in a final push to win over high numbers of undecided voters.
Three new opinion polls published in today's papers all suggested a very narrow majority supporting staying in the UK but also showed that the undecideds could swing it either way.
"I'm really optimistic that if we do have independence, we can start building a society that works for all of us," said 24-year-old Sam Hollick, a "Yes" activist from the Green Party who was campaigning at a stand on Edinburgh's Leith Walk blaring the hit song "500 Miles" by Scottish band The Proclaimers.
"I'm going to be reading up on it tonight," he said.
Also Read
"I'm going to be looking at what side makes the better argument, whether I can believe one side."
In a letter to the people of Scotland, pro-independence First Minister Alex Salmond urged the electorate to seize its historic chance to end the 307-year-old union with England.
"Wake up on Friday morning to the first day of a better country. Wake up knowing you did this -- you made it happen," Salmond wrote.
But Alistair Darling, a former British finance minister who heads up the "No" campaign, said there would be "faster, better change" for Scotland within the United Kingdom.
Britain's three main political parties have promised increased though unspecified powers for the Scottish government in the event of a "No" vote, including on taxes and social welfare.
"We have all built the UK together and we have benefited from that strength... I think it would be a tragedy if that relationship were broken," Darling told BBC radio.