It means the journey will now be direct for both directions of travel for the first time.
The rail operator has been operating direct services from London to the Dutch capital since 2018.
However, due to red tape, passengers couldn’t go through border control in the Netherlands.
Instead, it meant they had to make their return trip on a Thalys service via Brussels Midi to get their passports checked at the Belgian border control, before swapping trains to continue their journey with Eurostar.
In July, a treaty signed in Brussels by France, Belgium and the Netherlands finally allowed UK Border Force staff to be stationed in Amsterdam and Rotterdam, making the direct service possible.
Eurostar said that fares will start from £40 each way, with a journey time of 4h 9m from Amsterdam, or 3h 29m from Rotterdam.
Tickets are released six months in advance, which means from next week, passengers can book travel for up to February 2021.
For all journeys booked before 31 December, passengers can exchange fares without paying a fee up to 14 days before travel.