WPP shares surged after the advertising group said its key top-line metric fell less sharply last quarter, with Chief Executive Cindy Rose crediting her turnaround plan with driving a run of account wins.

Shares in WPP were up 24% in European morning trading Thursday, reversing losses earlier in the year to leave them up 13% since the start of 2026. If sustained until close, this would be the stock's biggest one-day percentage gain since 1992.

The London-based company said revenue less pass-through costs--a closely watched measure of its top-line performance--fell 2.8% on a like-for-like basis in the second quarter. Analysts had expected a 6.3% decline, according to consensus estimates compiled by Vuma.

This marked an improvement compared with the 6.7% drop WPP reported for the first quarter. The company attributed the recovery to better trends at its WPP Media business.

Rose said on a call with analysts that the result mainly reflected past account losses, but that recent account wins and retention of assignments with existing clients pointed to momentum building across the business.

The executive took the helm of WPP, home to agencies such as Ogilvy and VML, last year and set out to turn around its fortunes after a string of client losses hurt its performance and share price, while the rise of artificial intelligence stoked investors' fears about the long-term outlook for the business.

Since the start of the year, WPP won accounts from clients including Estee Lauder and Heineken and held on to existing relationships with others like Skechers and Huawei, which helped it top the industry's new-business ranking in the first half, according to a tally by J.P. Morgan analysts.

The company also offloaded some noncore assets, which it expects to generate 200 million pounds ($269.4 million) in proceeds this year, and signaled more would follow. Several sales processes are under way, Chief Financial Officer Joanne Wilson said.

Rose also said the company is on track with her turnaround plan, which contemplates a return to top-line growth over the course of next year.

WPP forecast like-for-like revenue less pass-through costs to decline by a low to mid-single digit percentage in the second half, following a 4.7% drop in the first.

The company had previously guided for like-for-like revenue less pass-through costs to decline in the mid to high-single digits in the first half, and to improve in the second.

For the first half as a whole, WPP made a pretax profit of 106 million pounds, up from 98 million pounds a year before. Net profit fell 57% to 19 million pounds.

Overall revenue fell to 6.37 billion pounds from 6.66 billion pounds.