Tamara announced her happy news with a touching picture of her newborn baby on Instagram. "Welcome to the world Sophia, our beautiful baby girl, born yesterday 6lb 9oz. Proudest day of our lives, never felt love like this. X," she captioned the shot of her looking lovingly at her daughter.
New mum Tamara Ecclestone posing with daughter Sophia
The news comes one year after the model and entrepreneur met and fell in love with husband Jay Rutland, a former City trader.
Speaking to HELLO! Tamara, who is the daughter of Formula One billionaire Bernie Ecclestone, said the arrival of her sister Petra's little girl Lavinia had made her broody.
"It opened my eyes as to how all-consuming motherhood is. Petra gets up with Lavinia in the middle of the night – she's such a great mum.
"It also gave me a reality check that it isn't just about buying cute baby clothes," she said.
Of course, as a fashion lover Tamara stocked up on a few garments ahead of time.
The pretty brunette, who announced the gender of the baby by posting a picture of a gold rattle in a pink box, picked out several snug looking rompers in pastel colours.
After being seen in Mothercare in February, she tweeted followers of her excitement at having an outfit for the baby to wear from hospital, adding the hashtag "#prepared".
The new parents got a engaged in Dubai after a whirlwind four-week courtship and celebrated their marriage last summer with a fabulous beachside party in St Tropez.
In early January, Tamara and Jay took a 'babymoon' in Gstaad to have some quality time together before starting their family.
Speaking about the anniversary of their introduction, she tweeted followers that it had been "the best most special year." "The best is yet to come. Feel so blessed," she added.
The 29-year-old is confident that Jay, 31, will throw himself into his new role. "He loves children and isn't selfish at all," she told HELLO! "I can totally see him getting up at night to help me."