The Institute for Fiscal Studies has published its written initial response to the Budget, adding figures to Helen Miller's earlier verdict that it has "very little that will move the dial on growth".
The IFS says higher borrowing costs cut headroom against the binding fiscal rule to £13bn before any new policy. Tax rises slightly larger than spending rises take it back to £15bn in 2029-30.
New giveaways push borrowing up by £8bn this year and £4bn next year, the IFS says. Borrowing in cash terms had been due to fall significantly from last year to this year. It is now set to be effectively flat.
"The biggest revenue-raisers involve making companies and Self-Assessment income taxpayers pay their tax slightly earlier."
The IFS says the £100 one-off payment goes to around 80% of households in England. It also says it was unexpected that the bank tax rise is only temporary.
It warns of a "clear risk" that the fuel duty delay and the electricity VAT cut, extended to July, will not actually be temporary. It adds that there was very little detail on how the government gets to 3% of GDP on defence by 2030.