If you are a BJ's Club™ or BJ's One™ Member, you may upgrade your Membership on BJs.com. 

1) Go to BJs.com/account/accountdetails and login

2) Hover over your name on the top right corner then select "Account Information"

3) Click on the "My Account" page, you will see the option to upgrade your membership at the top of page. 

4) Select "Upgrade", and you will be moved to a checkout page.