The quick answer
Turn on Vendor Access under Setup > Company > Enable Features, on the Web Presence subtab. Then edit the vendor, open its Access subtab, check Give Access and Send New Access Notification Email, select Vendor Center in the Roles sublist, click Add and save. The vendor logs in with the address in its Email field.
Your vendors email AP and purchasing to ask whether a PO is still open. The Vendor Center lets them look it up themselves. This example gives one vendor, Harborline Packaging, its own login and ends on what that vendor sees after signing in: its two open purchase orders. The person and operating-company names in the screenshots are fictional example data.
Before you start
Turning on the feature needs an Administrator. Granting access on a vendor needs a role that can edit vendors and give access. The example uses Administrator for both.
Check the vendor's Email before you start. That address becomes the vendor's user name, and the password setup email goes to it. Use an address only that vendor controls. Everyone who reads a shared mailbox shares the login, and an address that already signs in to another NetSuite account can make password setup messier.
External logins like this one are subject to your edition and contract. Check those limits before you give access to a lot of vendors.
In OneWorld, the vendor's subsidiaries also limit what it sees. A custom role with cross-subsidiary viewing widens that, so review the role before you assign it.
01. Turn on Vendor Access
Go to Setup > Company > Enable Features and click the Web Presence subtab. Scroll to the Access section. In this account Vendor Access is cleared. Its description says it lets you give vendors access to view open POs you've issued to them. Until it's on, vendor records have no Access subtab.
Check Vendor Access and click Save.
02. Check who can sign in today
Go to Lists > Relationships > Vendors. Harborline Packaging has Email orders@harborline.example and Login Access No. Nobody at the vendor can sign in yet. If your list view doesn't show Login Access, add the column to the view or use one that has it.
03. Open the vendor's Access subtab
Click Edit on Harborline Packaging. Under Email | Phone | Address, confirm Email is orders@harborline.example. That's the user name the vendor will log in with.
Click the Access subtab. A notice recommends sending a New Access Notification Email instead of typing a password yourself. Give Access is cleared, the password fields are empty and the Roles sublist has no lines. If a vendor already has Give Access checked or roles listed, review those first instead of granting again.
04. Give access and send the setup email
Check Give Access, then check Send New Access Notification Email. On save, NetSuite sends the vendor's Email an access notification with a link to set its own password. Whether it arrives is something you check separately.
Leave Manually assign or change password cleared. Password, Confirm Password and Require Password Change On Next Login stay empty. That way nobody on your side ever knows the vendor's password.
05. Add the Vendor Center role
In the Roles sublist, open Role, select Vendor Center and click Add. The line now lists Vendor Center as a committed row. Make sure it's there before you save. A role still sitting in the entry row hasn't been added. If your company uses a custom role based on Vendor Center, pick that instead.
06. Save and check the vendor
Click Save. The vendor opens in view mode and shows Vendor successfully Saved. Click the Access subtab. Give Access is checked and the Roles sublist lists Vendor Center.
07. Confirm on the Vendors list
Go back to Lists > Relationships > Vendors. Harborline Packaging now shows Login Access Yes. That confirms the saved setting. It doesn't tell you the email arrived, that the vendor set a password or that anyone has signed in.
08. See what the vendor sees
After setting a password from the email, Harborline's order desk logs in with orders@harborline.example. In this account the Vendor Center home says You are logged in as a Vendor of Example Supply Co.
In this account the home page has a Transaction Search portlet. The vendor sets Transaction Type to Purchase Order and clicks Search. Dashboards vary by role and account, so your vendors may see a different portlet for the same search.
In this example the results list PO2087 and PO2094, Harborline Packaging's own purchase orders. Orders placed with other vendors don't appear. Which orders a vendor sees in your account depends on its role and, in OneWorld, its subsidiaries. What else it can open, such as payment history, depends on the same things. Test with a controlled vendor login before you tell vendors what they'll see.
Common questions
Why doesn't my vendor record have an Access subtab?
Check that Vendor Access is on under Setup > Company > Enable Features, on the Web Presence subtab. If it's on and the subtab is still missing, look at your role's permissions and the vendor form you're using, since either can hide it.
Which email address does the vendor log in with?
The address in the vendor's Email field. Here that's orders@harborline.example. Fix the address before you check Give Access, because the setup link goes to it too.
Should I send the notification email or set the password myself?
Send the notification. Check Send New Access Notification Email and leave Manually assign or change password cleared, and the vendor picks its own password from the link. If you do set one manually, Require Password Change On Next Login makes the vendor choose a new one at first login. That box is a one-time flag and may not stay checked after you save.
Why didn't the Vendor Center role save?
Usually because Add never got clicked. Selecting Vendor Center in the entry row isn't enough. The role has to show as a committed line before you save, then it shows in the Roles sublist in view mode.
Can each contact at a vendor get its own login?
Don't count on it. This procedure gives the vendor record one login, tied to its Email field. Adding contacts to the vendor doesn't create separate Vendor Center users.
Does a Vendor Center login use a full user license?
It's a limited external role, but what counts against your limits depends on your edition and contract. Check with whoever manages your NetSuite agreement before you give access to a lot of vendors.
How do I remove a vendor's access?
Edit the vendor, clear Give Access and save. Removing one line from the Roles sublist doesn't end access while another role is still there.
What if the vendor never got the email?
Check the Email field for typos, then ask the vendor to look in spam or at its mail filters. Login Access Yes only tells you the setting saved. It doesn't prove the email arrived or that anyone set a password.