The TOWIE lovebirds had the honour of lighting up the Berkshire town when they arrived at Broad Street Mall on Saturday (14 November).
And they even got to meet Mr Christmas himself, Santa Claus!
Wrapped up against the cold wintry day, Lydia and Arg pressed down on the all-important switch and seemed super excited to be there.
Tweeting their fans after the event, Lydia said: "Such a festive evening. Thank you to everyone who came to see me and @real_arg switch the Xmas lights on in Reading."
Arg, in turn, wrote: "Christmas lights switch on in Reading with Mrs Claus @lydiabrighthaha! So excited for the festive season #itsthemostwonderfultimeoftheyear."
The night before Lydia and Arg had enjoyed a romantic meal at Japanese-Brazilian-Peruvian restaurant Sushi Samba in London.
The pair were enjoying their last hours together before Lydia jets off to Budapest and then Australia.
Arg expressed his emotions with his fans, saying: "Going to miss my @lydiabright so much when she goes to Budapest & Australia on Sunday! Send off meal at the amazing Sushi Samba #NeverCanSayGoodbye x."
Sharing a picture of their cosy evening, Lydia - showing off her new platinum hair - tweeted: "Date night with my Prince @real_arg #SushiSamba. Next stop Budapest."
Just days before, she'd got gushy when she wrote: "Don't give up on someone you can't go a day without thinking about. Love you to much @real_arg can't wait for our future #NannyPats80th#TOWIE #Finale."
Awwwww, could this couple get any cuter??!!
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