WE now know that George Osborne will be delivering the next Budget on 8 July. What we don’t know is what he will say.

The Conservative Party manifesto made a simple statement that if the party was elected, there would be no increases in VAT, income tax or national insurance. That simple statement is doubtless causing a few headaches at the Treasury where work will be underway to decide how funds will be raised to deliver on the various spending and tax reduction pledges (including those unveiled in the Budget in March).

Where might the Chancellor look? Perhaps it depends on how literally you take the words “no increases in VAT, Income Tax or National Insurance”. Does this simply mean no increases to the rates of tax? If it does then the actual scope of these taxes could perhaps still be extended (for example by restricting income tax reliefs for buy-to-let landlords or by applying VAT or national insurance to more items).

Paul Johnson, director of the Institute for Fiscal Studies has questioned the rationale for the 25% tax free pension lump sum on retirement; he has also said that employer contributions to pension funds are treated “absurdly generously” for national insurance. Would making changes here be contrary to the commitment not to increase income tax or national insurance? They would certainly raise significant sums of tax.

Should we look at taxes that are not covered by the manifesto pledge such as capital gains tax? This tax has, over the years, seen many changes and it would not be surprising to see more in July. In his first Budget after the 2010 election Mr Osborne made radical changes to it which took effect immediately.

Should we look at inheritance tax? We know that the government is committed to a new relief for passing on the family home, but will other reliefs remain unchanged?

In the Sherlock Holmes story Silver Blaze, the great detective solves the crime when he realises that the dog didn’t bark because it knew the culprit. I suspect that we need to think about the dogs that didn’t bark in the run up to the election and personally I will be looking out for more changes to tax reliefs on pensions, changes to capital gains tax and a tightening of reliefs elsewhere.

If you are relying on tax relief in any of these areas, I’d advise a chat with your accountant well before 8 July.

Paul Aplin OBE is a tax partner with A C Mole & Sons and chairman of the Technical Committee of the Institute of Chartered Accountants in England & Wales Tax Faculty; you can follow him on Twitter @PaulAplinOnTax. He and fellow tax partner Amanda Gunter can be contacted on 01823 624450.