Carlos Sainz has written a special letter to Williams staff after his first season with the team in F1 2025, it has emerged.
Sainz joined Williams ahead of the F1 2025 season after being forced to make way for Lewis Hamilton, the seven-time world champion, at Ferrari.
Carlos Sainz pens letter to Williams staff after successful F1 2025 season
While Hamilton failed to score a podium finish across his first season with his new team, Sainz came away with two by finishing third in Azerbaijan and Qatar. He equalled the result in the United States Grand Prix sprint race.
Sainz’s contributions helped Williams to fifth place in the constructors’ championship, the Grove-based team’s best result since the 2017 season.
Images have circulated on social media of Williams staff being presented with gift bags, which each contained an end-of-season letter penned by Sainz.
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In the note – described by the Spaniard as a “small gesture of appreciation” and “a reminder” of what the team achieved in 2025 – Sainz reflected on a “remarkable” first season with the team.
And he reminded his colleagues that “there is still a long road ahead” before Williams realises its “ultimate goal” of winning again in F1.
Sainz wrote: “Dear Williams Family,
“As we close out a remarkable first season together, I want to express my sincere gratitude to each and every one of you for the incredible welcome I have received since day one at Grove.
“I knew I was joining a very special team, but our first year together has exceeded all my expectations.
“This specially designed print is a small gesture of appreciation, and I hope it serves as a reminder of what we accomplished together during 2025.
“It is thanks to your dedication and commitment that we have been able to achieve our most ambitious goal this year: securing P5 in the constructors’ championship, while also having a bit of fun along the way with the podiums in Baku and Qatar, and the sprint podium in Austin.
“Those highlights are not mine they are a direct result of your efforts and our teamwork, and I truly hope you feel as proud as I do of every point we have scored.
“We have laid solid foundations for the upcoming season, and I cannot wait to go racing again.
“But make no mistake, there is still a long road ahead before we achieve our ultimate goal of returning this team to its winning ways, to where it belongs.
“After our first year together, I have no doubt that we have all the right ingredients to get there, and you can be sure I will give my absolute best to represent you on and off the track to the best of my abilities.
“Be proud of what we are building together, enjoy a well-deserved rest with your loved ones, and see you in 2026 with our batteries fully recharged and ready to go again.
“Vamos!”
How Carlos Sainz and Lewis Hamilton fared at their new teams in F1 2025
F1 2025: Head-to-head qualifying statistics between team-mates
F1 2025: Head-to-head race statistics between team-mates
Williams is expected to make considerable steps forward under the new F1 2026 rules, which will see the sport embrace 50 per cent electrification, fully sustainable fuels and active aerodynamics.
Sainz revealed in October that Williams’ use of Mercedes engines was one of the “main reasons” behind his decision to join the team after being forced to make way for Hamilton at Ferrari.
Hamilton wrote frequently to Ferrari all season having revealed in July that he has been sending a series of “documents” to Maranello in an attempt to turn the team’s situation around.
The documents are believed to contain suggestions to improve the car and the team, including improved communication between different departments and better execution of race weekends.
Hamilton told PlanetF1.com and other media outlets ahead of the Belgian Grand Prix that his willingness to take a hand-on approach is driven by his “refusal” to follow in the footsteps of Fernando Alonso and Sebastian Vettel, established champions who failed to win the title with Ferrari.
Earlier this week, former Ferrari team principal Maurizio Arrivabene aired reservations about Hamilton’s approach, arguing that it is a sign that the relationship between team and driver is “over” when “a driver starts playing engineer.”
Arrivabene, who famously told Vettel to stop interfering with off-track matters and focus on the driving during Ferrari’s winless 2016 season, told Sky Italy: “Sebastian Vettel also sent such dossiers. He wrote, spoke and shared everything.
On the value of Vettel’s documents to the team, he added: “Almost useless.
“I don’t want to say anything bad about Sebastian, but everyone should mind their own business.
“When a driver starts playing engineer, that’s it. Then it’s really over.
“Drivers spend two or three days in the simulator and get a general impression, but the devil is in the details.
“When the car is on the track, the driver must provide relevant feedback so that the engineers can make targeted improvements – especially when there is potential.”
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