MPs are to be allowed to increase their staffing budgets by up to £15 million a year in total.
The annual staffing expenditure limit of £115,000 will rise to £137,200 for non-London MPs and £144,000 for those representing constituencies in the capital.
The move, announced today by the Independent Parliamentary Standards Authority (Ipsa), could cost the taxpayer £15 million.
However, the expenses watchdog said it did not expect the bill to be so high because not all MPs claim up the current limit.
The move follows the annual review of MPs' allowances by Ipsa, set up in the wake of the expenses scandal to set, administer and provide independent scrutiny of claims.
Ipsa chairman Sir Ian Kennedy said the new expenses scheme was "stable and well established".
He added: "Following the review we have made a significant move to help MPs to staff their offices more effectively. This will help them in the service they provide to their constituents.
"Through our public consultation, I have seen some great examples of the skill, commitment and professionalism that MPs' staff offer.
"I think it is right for staff, MPs and indeed all people who look to their MPs for assistance, that we take these steps."
MPs who lose their seats if there is a snap general election before 2015 will also be in line for resettlement grants. They will be worth one month's salary for every year of service up to a maximum of six months, meaning the maximum award would be about £33,000. It will only be available to MPs who have fought for re-election and lost.
Previously all retiring MPs were entitled to between 50% and 100% of their salaries in the form of resettlement costs.
The resettlement grants announced today are an interim measure pending a review of MPs' overall remuneration, which will introduce longer-term arrangements by the time of the planned May 2015 general election.
There are currently only about 70 MPs, out of 650, who claim the current maximum staffing allowance or to within £5,000 of it, according to Ipsa figures.
Campaign group the TaxPayers' Alliance said it could see no justification for increasing the staffing allowance.
Political director Jonathan Isaby said: "It is entirely right that MPs should be afforded appropriate financial and staff support in performing their important duties, but Ipsa specifically acknowledges that even now the majority of MPs are not using their full staff funding allocation.
"So taxpayers will be confused - especially at a time when there is a public sector pay freeze - as to why an increase is being proposed for the staffing budget.
"When families, businesses, councils and government departments alike are all having to make savings, we cannot see a justification for an increase in staff expenditure: MPs too must have regard to the pressures on public funds."
Mr Isaby argued that defeated MPs should only get one month's salary and "not be expecting generous golden goodbyes".