Sometimes when we journalists say things like "this is no ordinary Budget", we do it to try to get you excited.
As in: "This is no ordinary Budget... it'll be chock full of so many measures it'll change your life forever. So pay attention!"
This week, when you hear someone say "this is no ordinary Budget", I'm afraid it means something else.
Unless Philip Hammond surprises us all, this will be a far thinner, less exciting Budget than most.
It might, by some measures, feel even less interesting than last November's Autumn Statement.
After all, back then we had yet to learn how the Office for Budget Responsibility would react to the Brexit vote (they did so by cutting the outlook for UK GDP growth this year from 2.2% to 1.4%).
This time around they will probably increase their in-year forecast a bit, but they are unlikely to map out the precise long-term impact of leaving the single market, since they can legitimately say there's no point in doing so until we know what kind of a deal we negotiate.
If I'm wrong on this, which is quite possible, then I take back the stuff above about this being a boring Budget.
The main reason this Budget will feel a bit like an Autumn Statement is because that's precisely what Mr Hammond wants.
When he became Chancellor he decided to change the political timetable so that the Budget would take place in the autumn, with the Autumn Statement moved to the spring.
For constitutional reasons (something to do with the political timetable) he couldn't cancel this year's spring Budget.
The upshot is that this Budget is a bit of a charade.
Yes, there will be some eye-catching stuff: more money for schools, more for social care and businesses struggling to pay their rates.
But if you're expecting any far-reaching reforms of the UK economy, you've picked the wrong event.
But that suits the Chancellor. Unlike most of his predecessors, Mr Hammond has shown little interest, thus far at least, in fiddling with the economy or pulling rabbits out of hats.
He does not see himself as a social reformer, like Gordon Brown and George Osborne.
But he would like to improve the tax system.
He would like to make it simpler. He would like, in the case of corporation tax, to make it work.
Such things take time, and lots of forethought.
So while this Budget won't change the state of the economy overnight, it might give us a hint of the direction of travel.
We may get promises of a big look at social care and at corporation tax - though for the time being that means commissioning some new reviews rather than actually doing anything.
However, the main priority at the Treasury this month is to do as little as possible.
Before you assume that that makes this a total non-event, don't be fooled.
For beneath the surface some important political manoeuvrings are occurring.
While the Treasury is still determined to try to reduce the deficit as quickly as possible, the same thing could not be said about Number 10.
So in an odd way, the less extra spending there is tomorrow, the bigger the achievement from the Treasury's perspective.
Keep a particular eye on how much of the deficit reduction gets banked by the government - and how much gets spent.
If the majority is left in the bank, that means Mr Hammond has won a very important battle indeed.
The more boring it is, the better he is doing.
:: Sky News will have live coverage and analysis of the Chancellor's Budget from 12.30pm, with a special programme starting at 10am.