On their website, Pret names these items as vegan:

Miso Sweet Potato Banh Mi, Asian Greens Veggie Pot, Chipotle Corn & Avo Veggie Pot,
Chakalaka Wrap, Asian Tofu Sushi Salad, Turmeric Tofu Balance Box, Mediterranean
Mezze Salad, Spicy Black Bean and Mango Wrap, Carrot Turmeric Soup, and Almond Matcha Latte

For more information, see https://www.pret.com/en-us/not-just-for-veggies

There are Prets in Boston, Chicago, New York City, and Washington DC.

For information about eating at other restaurant chains, see:
http://www.vrg.org/fastfoodinfo.php

To find vegetarian and vegan restaurants, go to:
http://www.vrg.org/restaurant/index.php

The contents of this posting, our website and our other publications,
including Vegetarian Journal, are not intended to provide personal
medical advice. Medical advice should be obtained from a qualified
health professional. We often depend on product and ingredient
information from company statements. It is impossible to be 100% sure
about a statement, info can change, people have different views, and
mistakes can be made. Please use your best judgement about whether a
product is suitable for you. To be sure, do further research or
confirmation on your own.