*NEW* Now See All Your Electronic Travel Credit(s) (ETCs) on Your United.com Account!
Update 30 Aug 2021
See discussion in COVID19 Schedule Change (6+hrs)/Cancellation Refund, UA resisting refunds, DOT ruling

Checking the balance: http://www.united.com/web/en-US/apps...s/default.aspx
Enter type (see below) and PIN as a single code without any spaces. Then the page will say it couldn't find anything and offer you a place to enter your last name. Note, will show remaining value but not expiration date,

What does "type" mean? Good question. See the following answer from post 670:

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Electronic Travel Certificates (ETCs) / vouchers can only be used for travel on an entirely UA/UX operated paid itinerary.
Late August 2021 Now useable on partner and codeshare itins!
ETCs can now be used to pay pre-paid baggage fees.
Not valid when there are partner flights or any segment that uses partner metal.
Cannot be used to pay award flight fees.
Cannot be used for E+ fees, WiFi fees, UA subscriptions (Wifi, E+ fees, UC membership, ...), upgrades fees (but OK for up-fares), change fees, ....
ETC can be used by anyone with the PIN and last name of the original person receiving the ETC.
If not fully used the residual can be used later with the same original expiration.
ETCs will be used for the total amount needed (no partial payments if the ETC has a greater value)


TVCA certs with PINs (by far the most common ecert most customers will receive -- such as goodwill compensation from Customer Care or refunds on flights) are considered a form of payment and don't reduce the PQDs PQP earnings.. So the full value of the ticket is earned, no reduction
Expiration -- ETCs generally have a 1 2-year life. The ETC should be used prior to expiration -- but the actual travel days can be after expiration. While not publically documented, it does appear ETCs have a 30 day (one month?) post-expiration grace period.

How do I use the ETC?
Online works fine or you can call and used an agent (a fee may apply)

Online, either select "all search" options and scroll to the bottom of the screen to enter
or
wait until you get to the Payment Options at the end of the purchasing steps and select "United payment types"
Enter pin code (7 or 10 digits) and Last Name on the ETC

Where online can I view my unused ETCs?
You cannot. No such listing is available. UA now displays some ETCs in Your Account (May 2020)
Reports suggest ETCs from flight credits seem to be displayed but customer service ETCs are not.
Now See All Your Electronic Travel Credit(s) (ETCs) on Your United.com Account!
You can call and ask an agent to look these up for you. Note agents will not provide the ETC PIN on the phone.

Can an ETC be used for covering the costs of a post-purchase upfare?
Multiple reports of success but one mentioned it would need to be the sole method of payment.
Can only be done by an agent -- not online
Can not be an upgrade fee, must be an upfare.

Can an ETC be used to UC membership or E+ access fee or change fee or award fee or upgrade co-pay or baggage fee or ...
ETCs can only be used for airfare, not for any fee
August 2020 - ETCs can be used for internet access, E+, subscriptions, upgrades, bag fees

Can I partially use an ETC and then pay the remainder with a credit card (to get the card's benefits)?
No, the ETC must be fully used (up to the needed amount). Only if the ETC is insufficient, can a credit card then be used.

If I make a booking with an ETC and then cancel -- what happens?
Normally it would just stay as flight credit. If refunded, it goes back to the original ETC (recent reports suggest a new ETC is now issued). If that has expired, it gets tricky, UA may create a new ETC -- this situation generally takes manual handling. It does not get converted to cash

How many ETCs can be used at one time?
There is a limit of one ETC per passenger. If you have multiple passengers on the PNR, you can apply 1 ETC each ( does not have to be the same value ETC nor does ETC to be applied to every passenger). (Recent reports suggest the use of multiple ETCs per passenger). If you have more ETCs than passengers, you can now combine ETCs. You can also use one-ways to double the number of opportunities to use ETCs vs roundtrips.
Combinability update July 2017 - ETCs can be combined (either a new ETC created with the expiration date of the earliest-expiring ETC or multiple ETCs used on a PNR). Appears will only combine ETC if you need to do this to book a flight. Initially, UA seemed to allow the combining for future use but most reports now suggest you need to also have a flight booking in mind using the new combined ETC.
Combinability update June 2020 - ETCs can be combined at the website payment screen without calling (see post 690)

Related threads
Extending a Credit/Travel/ETC Voucher by booking a refundable fare?

Is there any way to combine multiple travel certificates into one? {out-of-date -- see not above}

UA Electronic Travel Certificate & Codeshares/partner flights

Using ETCs in Canada (outside of US) on new United.com

Archive: UA Electronic Travel Certificates (ETC): General Q&A, ... {Archive}