Partridge was handed a place on the plane to Russia after setting a new personal best of 2:30:46hours at the London Marathon to finishing as the highest British female.
That was three minutes better than her previous effort and 14 seconds inside the A standard for the World Championships with Samuels' mark from the Berlin Marathon last year good enough.
Samuels didn't take to the London course but her time of 2:30.56 from Berlin is also inside the A standard and British Athletics head coach Eriksson has plenty of confidence in the pair.
"The performances at the weekend were very encouraging and I'm delighted to be able to select Susan Partridge and Sonia Samuels to represent GB & NI at the IAAF World Championships," he said.
"Our endurance programme has already made a lot of progress and I'm confident that both athletes will perform well in Moscow and enable us to continue moving forwards."