Three items you need to start:

  1. Computer with Internet access
  2. Confirmation or E-ticket number
  3. Credit card or United Mileage Plus card

Like most other major carriers, United Airlines makes it tough for customers to use paper tickets. You can still do it, but requesting a paper ticket at the time of booking or after the fact prompts a $50 transaction fee, according to United's website. United offers several ways for travellers to check-in and get a boarding pass for their E-ticket.

EasyCheck-in Online

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Go to the United Airline's website. If you are a member of United's Mileage Plus frequent flier club and have an account set up online, log-in using your Mileage Plus number or email address and password.

Alternatively, you can sign-in as a guest using your last name and one of the following: the credit card number used to purchase your ticket, your itinerary's confirmation number or your E-ticket number.

1. Enter your information

Select your seats, add your Mileage Plus number, request an upgrade, enter baggage information and pay any associated baggage fees in advance online.

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Print your boarding pass immediately. You also can wait and print your boarding pass at the airport using an United EasyCheck-in Kiosk. Check your bags, if you have any, and proceed through security to your flight. Note that United's EasyCheck-in Online is available 24 hours ahead of your flight's scheduled departure time. The service closes 45 minutes before scheduled departure time for domestic flights and one hour before international journeys.

2. EasyCheck-in Kiosk

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Arrive at the airport and look for an United EasyCheck-in Kiosk. United's website notes that, as of March 2010, the kiosks are widely available at every major United hub. More than 1,000 kiosks are in operation at more than 100 airports.

3. Swipe a major credit card

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Swipe a major credit card in the United EasyCheck-in Kiosk. The name on the card must match the name on your E-ticket. The following Mileage Plus cards can be used in lieu of your credit card: Mileage Plus Premier, Premier Executive or 1K cards.

Check Bags is Next

Follow the instructions on-screen, which include options for checking bags. If you are checking a bag, you must wait for an United representative to assist you. The representative will check your ID, tag your bags and provide you with a baggage claim ticket.

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Wait for your boarding pass to print. Proceed through security.

United's website notes that the EasyCheck-in Kiosk system provides you with several options, including the ability to request stand-by for an earlier flight and process and issue a boarding pass for flights delayed or cancelled due to weather and other abnormalities.

You can still proceed to an United Airlines ticket counter to receive a boarding pass for your E-ticket. Due to the availability of the online process and kiosks, this practice is becoming less common.