Skip to content
English
  • There are no suggestions because the search field is empty.

2.0 Custom UID Guide and FAQ

Match students across SSO and your LMS by ID instead of email. See who needs it, how to set it up, and what each status means

 
Custom UID identifies people by a stable ID from your school or company (student or employee ID) instead of by email. Poll Everywhere receives that ID from two places, your SSO and your LMS, and the value has to be the same in both. Once you turn on Identify with Custom UID, Poll Everywhere links the two even when the emails differ, for example a student who uses a personal domain in the LMS and a school domain for SSO.
The ID comes from two places and has to be the same in both:
 
SSO: an attribute from the identity provider (IdP) mapped to custom_uid in the Authentication settings.
 
LMS: the ID the LMS already holds for each person (Canvas calls it the SIS ID, Brightspace the Org Defined ID, Blackboard the Batch UID, and Moodle the ID number.)

Is Custom UID right for you?

Answer these in order. Stop at the first "No".
  1.  Is an LMS (e.g. Canvas) connected to Poll Everywhere? No: Custom UID isn't available for you yet.
     
     
  2. Do people sign in with SSO? No: Custom UID needs SSO, so it isn't available without it.
  3. Do SSO and LMS emails ever differ or change? No: not needed.
  4. Does the same ID exist in both your SSO and your LMS? No: set up a shared ID first.
  5. All yes: Custom UID is a good fit.

Good fits

  • People sign in with an email on a different domain than the one Canvas has (e.g. students.school.edu vs school.edu)
  • Name changes
  • Status changes: student becomes staff, undergraduate moves to graduate
  • Emails that get reassigned or aliased

What it does

Poll Everywhere gets an ID from your SSO at sign-in, from your LMS on roster syncs (automatically, or when an instructor clicks Sync roster) and when someone opens Poll Everywhere from a course. Once you turn on Identify with Custom UID, a roster entry or LMS launch carrying the same ID as one person's SSO sign-in is linked to that person, even if the emails differ, so their coursework and grades stay together
 

How the setup works 

  • SSO (usually your IdP admin): first make your identity provider send the ID field (for example studentId) in its sign-in response. Then in Poll Everywhere, go to Organization settings > Authentication > SSO connection > Attribute mappings, choose Edit attribute mappings, and map custom_uid to that field. Steps differ by provider (Google, Entra, Okta etc.), so check your provider's documentation for adding a custom attribute.
  • LMS: each person needs the same ID in your LMS: the SIS ID in Canvas, the Org Defined ID in Brightspace, the Batch UID in Blackboard, or the ID number in Moodle.
  • People sign in through SSO once so we get their ID. Setup ends at a locked switch. It unlocks only after one person signs in with SSO and then opens Poll Everywhere from a course in the LMS while still signed in, with the same ID from both, within 7 days. And because the ID is read only at sign-in, anyone already signed in has to sign out first.
  • In Organization settings > LMS connections, choose Set up under Custom UID. You'll see it once an LMS is connected, if you can manage both users and LMS connections.
  • Review, then switch on Identify with Custom UID.

Turning it on safely

  • Off (gathering data): we only observe. Matching, grades and launches still use email. You see what would happen, based on your course rosters and the last 7 days of sign-ins.
  • On: from each course's next roster sync, students are linked to their SSO accounts by Custom UID, or by email if they don't have one. If we created an account from someone's roster email and nobody has used it, we merge it into their SSO account automatically; this can't be undone. The page shows “On since <date>”. You can switch it off again: that stops matching new people by Custom UID, and people already matched stay with their accounts. If someone was matched to the wrong account, contact support.

Reading the Custom UID page

  • Where Custom UIDs come from: SSO coverage (e.g. 4 of 5 people who signed in) and LMS coverage (e.g. 5 of 5). Gaps explain who can't be matched yet.
  • People tabs: Needs attention, Matched, Not matched and All, each with a count and a status color. Search by name, email or Custom UID. Download N people as CSV exports everyone in the current tab and search.

Statuses

Status
 
 
 
Color
 
 
Meaning
 
 
What to do
 
 
Matched tab
 
(Matched)
 
 
Green
 
SSO and your LMS sent the same ID, and the emails match
 
Nothing
 
Matched tab
 
(Matched by Custom UID)
 
 
Green
 
Same ID, different emails (or your LMS sent no email)
 
Nothing; Details shows both sides
 
Not matched tab
 
(Waiting for SSO)
 
Gray
 
They opened Poll Everywhere from your LMS, which sent their ID, but haven't signed in with SSO since
 
Nothing; confirmed when they sign in with SSO
 
Not matched tab
 
(No recent sign-in)
 
 
Gray
 
Your roster has their ID, but they haven't signed in recently
 
Nothing; sent the next time they sign in with SSO
 
(Not matched tab)
 
Not in Poll Everywhere
 
 
Gray
 
On a course roster, but has no Poll Everywhere account
 
Nothing; the next roster sync adds them
 
Not matched tab
 
(Not on a roster)
 
 
Gray
 
Has an ID, but isn't on any synced course roster
 
Usually nothing; sync the roster if they should be on it
 
Needs attention tab
 
(Can move to SSO email)
 
 
Amber
 
On the roster under another email; their ID belongs to an SSO account
 
Same person: Move enrollment. Different people: correct the ID in your LMS
 
Needs attention tab
 
(Enrolled under another email)
 
 
Amber
 
As above, but the move isn't available yet
 
Follow the card: turn on matching, or contact support if it lists blockers
 
Needs attention tab
 
(Two emails in Poll Everywhere)
 
 
Amber
 
The email on their roster entry belongs to another Poll Everywhere account
 
If the roster email is wrong, correct it in your LMS. If both are theirs, nothing to fix
 
Needs attention tab
 
(More than one Custom UID)
 
 
Amber
 
SSO and your LMS sent different IDs
 
Decide which is right; fix the other in your IdP or LMS
 
Needs attention tba
 
(Not confirmed by SSO)
 
 
Amber
 
Your LMS has their ID and they signed in recently, but SSO sent no ID
 
Check your IdP has the ID and maps it to custom_uid; they then sign out and back in with SSO
 
Needs attention tab
 
(No email from (LMS))
 
 
Amber
 
Your LMS didn't share an email for them
 
Add an email to their LMS profile
 
Needs attention tab
 
(No Custom UID from (LMS))
 
 
Amber
 
Your LMS sent no ID for them
 
Add the ID in your LMS. Canvas: check the developer key's privacy level is Public
 
Needs attention tab
 
(Shared Custom UID)
 
 
Red
 
Two or more people signed in with SSO with the same ID, so it isn't used for any of them
 
Find out whose it is; correct the others in your IdP or student information system
 
 

FAQ

  • What is a Custom UID?
A unique ID from your institution that identifies a person regardless of email.
  • Why do I need it if matching by email works?
Email changes (names, domains, status changes) can create two accounts for one person. A stable ID keeps scores and grades with the right person.
  • Does it work without an LMS?
Not currently. It needs an LMS connected.
  • Does it work without SSO?
It needs SSO to send the ID.
  • Which LMS?
Canvas, Brightspace, Blackboard and Moodle, connected to Poll Everywhere with LTI 1.3.
  • Where do I find the ID in my LMS?
It's the SIS ID in Canvas (People > SIS ID), the Org Defined ID in Brightspace, the Batch UID in Blackboard, and the ID number in Moodle.
  • What if some people don't have an ID?
They are matched by email, as before.
  • Do I have to turn it on right away?
No. Leave it off to review matches first.
  • What happens to existing data when I turn it on?
  1. Nothing changes the moment you turn it on. At each course's next roster sync, students are linked to their SSO accounts by Custom UID. If we created an account from someone's roster email and nobody has used it, we merge it into their SSO account automatically, and that can't be undone.
  2. If someone already opened Poll Everywhere from your LMS under their roster email, they appear in Needs attention as “(name) is on the roster under another email”. If it's the same person, choose Move enrollment to (SSO email). Their course work moves with them, and this can't be undone either.
  • What's the difference between "Not on a roster" and "Not confirmed by SSO"?
The first has an ID but isn't in any synced course. The second is on the LMS roster, but SSO sent no ID.
  • Someone shows "More than one Custom UID". Which one is right?
Only you can tell. Check your IdP and Canvas, correct one, and have them sign in again.
  • I fixed an ID but the status didn't change.
Have the person sign in through SSO again, or sync the roster, and re-check.
  • Can I export the list? 
Yes, "Download all N people as CSV" on the People section.
  • I'm not the SSO or LMS admin. What do I do?
Send the "Needs attention" details or the CSV to your SSO and LMS admins; each card says what to fix.
  • How long do you keep the data?
  1. IDs from SSO sign-ins and LMS launches: while Identify with Custom UID is off, each is deleted 7 days after we last receive it. While it's on, we keep them; if you turn it off, the 7-day limit applies again.
  2. IDs on course rosters: your LMS sends the ID with each roster sync, and we store it with the person's roster entry, alongside their name and email, for as long as they're on a course roster connected to Poll Everywhere. This doesn't depend on the setting.
  • Who do I contact?

If you have any questions or run into issues, please send an email to support@polleverywhere.com