The introduction of fixed-term parliaments has removed all mystery about when voters will get their say at the ballot box. We can all prepare well in advance for polling day – either by clearing our diaries in excitement (me) or booking a foreign holiday in despair (quite a few others).

But while this means we all know the election will be on 7 May 2015, it also means we know some of the events that will take place between now and then. And the path to polling day is not a pleasant one – for any of the main parties.

Here are 10 key dates that are likely to shape the political landscape of the next 12 months. Mark them in your calendar now…

22 May: EU and local elections

An enormous challenge for the main parties. Seats are being contested in every London borough plus dozens of towns, cities and districts across England. Many are in areas Labour must do well in come the general election to stand any chance of forming the next government. The Tories and Lib Dems will be desperate to avoid big losses, though given the relatively small number of Tory “heartlands” up for grabs, David Cameron will want to keep expectations low. Elections to new councils in Northern Ireland are also taking place.

Meanwhile the EU elections pose an opportunity for Ukip to come good on its rhetoric, embarrass all other parties and top the national poll… or else flop thanks to a mixture of over-ambition and hubris. The results of the EU poll won’t be declared until 25 May, to coincide with results across the rest of the continent.

4 June: the last Queen’s speech of this parliament

What laws will the coalition try and pass during the final 11 months of its life? There will be little time for the government to have any significant impact on voters’ lives before the general election. But it won’t want to give the impression that it has run out of steam, or that Tory and Lib Dem ministers are already fighting mutually exclusive election campaigns.

5 June: Newark by-election

Just one day after the Queen’s speech, the voters in the constituency of Newark will get a chance to deliver a snap verdict. Patrick Mercer’s resignation has created a by-election whose outcome, whatever the result, will not be dull. A Ukip gain would be a shock and arithmetically sensational: this is a very safe Tory seat. A Conservative hold would be fascinating as much for the margin of victory as for its consequences on morale in the other parties. And a Labour win would be startling but not beyond possibility, if Ukip splits the Tory vote and Lib Dems vote tactically.

18 September: Scottish independence referendum

The consequences of Scotland voting to leave the UK are incalculable, and that’s not just hyperbole. Nobody knows precisely what would happen – aside from an independent nation coming into existence, probably in 2016.

What is clear is that a “yes” vote would be a humiliation for David Cameron, who’d be known for evermore as the man who broke up the union. But a “no” vote would be a triumph, not just for him but the leaders of all anti-independence parties, including Ed Miliband and Nick Clegg.

Conversely, a “no” outcome would be a devastating blow for Scotland’s first minister and SNP leader Alex Salmond – but a man of his cunning will surely have a plan for dealing with just such an outcome. And you can be sure he’ll do his utmost to keep that plan a secret from Cameron and co.

23 September: Ed Miliband’s Labour conference speech

What timing: just a week after the referendum, the Labour leader will have to deliver his star turn while potentially facing the disappearance an electorate that, in 2010, supplied the party with 40 MPs. In 2012 Miliband made a splash with his “look, no script”/One Nation pitch. He scored another hit in 2013 with his surprise energy price freeze pledge. Will he pull off a similar trick this time? He’ll certainly need to come up with something to give Labour some pre-election momentum.

3 December (tbc): George Osborne’s autumn statement

Who knows what state the coalition will be in by now, just months away the general election. But here is one last chance for George Osborne and David Cameron to woo some Tory votes. Benefits slashed? More money for roads and houses? Perhaps even hints of tax cut? Whatever is announced will set the mood for the start of the campaign.

31 December: last UK troops to leave Afghanistan

The year will conclude on a sombre if historic note. A 13-year mission comes to end when the last British troops leave Afghanistan and return home. At the time of writing, 453 British soldiers have been killed in the country since the war began in 2001. During a visit to the troops in Helmand in December 2013, David Cameron said the British mission in Afghanistan had been “accomplished”. 2015 will prove whether his assessment was accurate or premature.

27 January 2015: GDP estimates for 2014

Here’s when we’ll get a first sense of the real scale of Britain’s economic recovery. The Office for National Statistics will release its initial estimate for GDP during October-December 2014, which in turn will give an indication of growth for the whole 12 months. In his last Budget speech, George Osborne predicted GDP to grow in 2014 by 2.7%. He’ll have given a revised forecast in his autumn statement in December. The latest figures will be a chance for the government to remind voters of the strength of the recovery, and a challenge for Labour to come up with a constructive line of attack.

18 March 2015 (tbc): George Osborne’s final Budget

It’s too late for any announcements to have a real impact on voters, save a bit of shameless chopping of duties on alcohol, fuel or tobacco. This will be more to do with sending a message to the electorate about trust and competence, albeit one sprinkled with a few airy pledges about what may or may not happen were a Tory government elected in six weeks’ time.

6 April 2015: start of the new tax year

Of all the things to happen during the run-up to polling day, this will arguably have most resonance with the public. The income tax personal allowance goes up to £10,500 today: something the Lib Dems have long campaigned for and about which they’ll undoubtedly trumpet. The 40% rate of tax threshold, which went up to £41,865 in April 2014, is due to rise by 1% at some point during 2015-16; we may have a clearer idea on a date by now. The inheritance tax threshold will now be frozen at £325,000 until April 2018, while corporation tax falls from 21% to 20%.

All of these changes, though not a surprise, are practical things the coalition will be able to point to as proof what they have done in government. That makes a big difference from talking about what you’d like to do – which will be both the curse and the blessing of the ensuing election campaign.