Elections are taking place today across England, Scotland and Wales - just a few weeks before the general election on June 8.
Here's everything you need to know, including the key times to watch out for.
What are people voting for?
There are 4,851 council seats being contested in England, Scotland and Wales. Voters in various parts of the country will also be choosing six new metro mayors.
What's at stake?
The local elections across the country are a test of Labour leader Jeremy Corbyn's popularity and also the future of UK Independence party.
The academics Colin Rallings and Michael Thrasher predict big gains for both the Conservatives and LibDems, with Labour suffering losses of up to 50 seats.
In 2013, Ukip surged in the polls, but this time they will contest just 48 per cent of council seats.
The Green party is contesting candidates in 53.9 per cent of seats, while the Conservatives will contest 96 per cent, and Labour will run in 91 per cent.
The Lib Dems, who have seen a surge in support since the EU referendum, will field candidates in 80 per cent of wards.
10pm tonight - polling stations close
Polling stations opened at 7am this morning and close at 10pm tonight, so you've got time after work to head to the ballot box. However don't expect any results straight away. The first one isn't expected to drop until 2am (Isle of Wight, in case you're wondering).
Early hours: Key Welsh councils
Labour are more secure in Wales by virtue of the fact that they hold large majorities in the areas where they're in control, but everyone will be watching to see how well the Tories do here ahead of the general election.
If Theresa May's party do triumph here, they could seize full control in Monmouthshire and threaten Labour in Newport and the Vale of Glamorgan. Bridgend and Wrexham will also be interesting. Labour stronghold Swansea will be first to declare.
You'll need to stay awake though, most of the key Welsh results are expected to drop in the small hours.
- Swansea - result expected 2:00am, Friday
- Wrexham - result expected 2:30am, Friday
- Newport - result expected 4am, Friday
- Merthyr Tydfil - result expected 4am, Friday
- Bridgend - result expected 4am, Friday
- Monmouthshire - result expected 5am, Friday
- Vale of Glamorgan - result expected 7am, Friday
5am: West of England mayoralty
There are six candidates battling it out for the first metropolitan mayor for the West of England, who will represent Bristol, Bath, North east Somerset and south Gloucestershire.
Tory Tim Bowles is the favourite, but will he get enough countryside votes to secure a win, or will traditionally Lib Dem Bath mean Stephen Williams takes the top job? It will be tough for Labour’s Lesley Mansell unless his supporters in the city of Bristol come out in force to vote.
This will be an interesting traditionally Labour-dominated council to watch out for on the way to work tomorrow morning - it could go to the Tories for the first time since 1981. No one party has had overall control of the council since 2001.
8am - 1pm: Not much happens
It all goes fairly quiet in the morning so you might as well do some work - but check back around lunchtime as more results start to trickle in.
Devon and Hertfordshire are among those revealing their results about 1pm, although the Tories are expected to keep hold of these.
2pm to 5pm: Flurry of results
The real national picture will begin to emerge around now as more and more results flood in, especially from Scotland.
Scotland was the scene of a spectacular collapse in Labour support at the 2015 general election with Ed Miliband's party losing 40 seats to the SNP. A similar bloodbath looks likely today when all 1,223 Scottish council seats are up for election. Of particular interest will be places like Inverclyde, Midlothian and East Lothian.
Glasgow City Council looks particularly vulnerable for Labour. Their lead over the SNP here is just 12 seats and, given the huge swing the SNP enjoyed in the city in the 2015 general election, this could be easily wiped out.
The Conservatives could also gain ground in Scotland and local and general election polling suggests they will. Dumfries and Galloway and Aberdeenshire will be councils to keep an eye on.
- Inverclyde - result expected 2:00pm, Friday
- Midlothian - result expected 2:00pm, Friday
- Dumfries and Galloway - result expected 2:00pm, Friday
- East Lothian - result expected 2:30pm, Friday
- Renfrewshire - result expected 2:30pm, Friday
- Aberdeen - result expected 3pm, Friday
- Glasgow - result expected 4pm, Friday
Over in England, Cambridgeshire will be interesting to see how well the Lib Dem fight back has gone. Since the 2013 local elections, no party has overall control of the council, with the Conservative group running a minority administration.
Meanwhile, if Labour lose control of its Midlands councils Nottinghamshire and Derbyshire it may well spell doom for the party in these areas in the forthcoming general election
Cornwall has been led by a coalition of Liberal Democrats and Independents since 2013 - but can the Lib Dems take full control?
- Cambridgeshire - result expected 2pm, Friday
- Oxfordshire - result expected 3pm, Friday
- Cornwall - result expected 3pm, Friday
- Derbyshire and Lancashire - results expected 4pm, Friday
- Nottinghamshire - result expected 5pm, Friday
6pm Friday: West Midlands and Greater Manchester mayoralties
There are eight mayoral positions up for grabs in England and Labour is expected to claim victories in Manchester and Liverpool, although the Tories have their fingers crossed in the West Midlands with Andy Street, former managing director of John Lewis.
We'll have to wait until 6pm tomorrow for results to come in from Greater Manchester and the West Midlands though. The result in the Liverpool mayoral election will come a bit earlier, at about 3pm.
How can I follow the results?
The Telegraph's political team will be covering all the results they come in and explaining what it all means.
Which areas are most important?
Based on the 12-point swing against the party since the last time these elections were fought in 2013, the analyst John Curtice predicts Labour will lose control of both Nottinghamshire and Derbyshire councils.
Labour are also predicted to suffer even more losses to the SNP in its former heartlands.
Here are the number of seats each party are defending:
- Labour- 1,535
- Conservatives- 1,136
- Lib Dems- 484
- SNP- 438
- Plaid Cymru - 170
- UKIP- 146
- Green Party - 34
Tell me more about the mayoral elections
Metro mayors will be elected in the six city regions that secured devolution deals- they will have new transport, housing and job creation powers.
The regions are Cambridgeshire and Peterborough, Greater Manchester, Liverpool City Region, Tees Valley, West Midlands and West of England.
Candidates to watch include the former shadow home secretary and Labour MP Andy Burnham- who is running in Greater Manchester.
Andy Street, the former managing director of John Lewis, who is standing as the Conservative party candidate in the West Midlands.
And Steve Rotherham, the Labour MP and former aide to Jeremy Corbyn, who is running in Liverpool.
Where can I vote?
You should receive a polling card through the post. The polling card is the easiest way to find out where to vote as it should include the name and address of the polling station for your district.
If you have not received your polling card, you can contact your local authority to find out where to vote. You can find the contact details for your council by visit the About My Vote website.
Polling stations are open from 7am to 10pm on polling day and you will usually find them in public buildings like local halls or schools.
Do I need my polling card?
No, don't worry if you lose your card. As long as you're registered on the electoral roll and go into the polling station and give your name and address, you will be able to vote.
Do I have to vote?
No, not in the UK. But there are a number of countries around the world where you can be fined for not casting a vote.
In Australia you can receive a financial penalty for failing to have you name marked off the electoral roll. You do not have to choose a candidate or a party, but the ballot paper must be "marked".
Why are elections held on Thursdays?
The last time a British election was not held on a Thursday was in 1931 when polling was on a Tuesday– in the midst of the Great Depression.
Thursday is the traditional market day in the UK - when most people are bustling around in their local town.
When will the general election be held?
Theresa May said she will go to the country on June 8. The Prime Minister told the Queen in a phone conversation on Bank Holiday Monday.
Parliament is likely to be dissolved on May 3. which will allow for an election campaign lasting for just over a month.