Clubs in excess of their league-imposed spending limit for the season -- which includes Barca -- will now be able to spend 50% of anything they save or raise on signing new players.
In addition, if the saving they make on a departing player accounts for more than 5% of their spending limit, they will be able to invest 60% on incomings.
Under the previous rules, clubs could only spend 40% of the money they saved or raised, rising to 50% if the saving on a given player was substantial.
"The objective [of the change] is to stimulate signings at a time when the transfer window is at a standstill while ensuring clubs are still making savings overall," a LaLiga spokesman said.
"This transitional change for the 23-24 season will positively affect many clubs in excess of their limit as they will be able to continue to operate in the market while making savings."
A league source said the change was for "all clubs as quite a few are in excess of their caps" and was not specifically related to Barca's existing financial situation.
The tweak to the rules was approved by the league's delegate commission, which includes the LaLiga president Javier Tebas, his vice presidents and representatives from 12 different clubs.
However, it cannot be denied that Barca will be one of the beneficiaries of the adjustment as LaLiga look to help clubs compile their squads for next season.
The Catalan club needed to cut around €200 million ($218.99m) this summer to comply with their spending limit -- which is expected to drop from around €650m to €450m -- although they have already made significant savings with the departures of Sergio Busquets and Jordi Alba.
They have also made cutbacks in other areas, such as closing Barca TV and reducing the wage bill of the basketball team (which is included within their spending cap), in a bid to help them register contract renewals and new signings when the transfer window officially opens in July.
Midfielder Gavi's new deal has been temporarily registered with LaLiga following a court ruling in Barca's favour, but contracts for Ronald Araujo, Marcos Alonso, Inaki Pena and Sergi Roberto are yet to be officially inscribed.
In addition, Barca this week announced the signing of Ilkay Gundogan as a free agent from Manchester City, with sources telling ESPN that defender Inigo Martinez will also join the club when his contract with Athletic Club expires on June 30.