Things changed here in the USA as of April 19 2022.
A new amateur radio license costs $35.
The 10 year renewal of an expiring amateur radio license also costs $35.
  https://www.fcc.gov/wireless/systems-utilities/universal-licensing-system/wireless-fees/personal-service-and-amateur
  https://www.arrl.org/fcc-application-fee

The first thing needed is FRN so payment is possible when needed.
Renewal is done via ULS and last check was free.
ULS is the way to all things FCC for licensing and such.

Not an expert only do it about once every 10 years.

Allison
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Please use the forum, offline and private will go to bit bucket.

Yup, I know somebody with a license expiring in a couple months.
Thanks!

Joe,

Don' t be sorry. This is relevant information.

Thanks,

Mike N2MS

Sorry, I posted this to the wrong group, please ignore if you wish. 

Hello all. I decided to start this thread to tell you what I know about the current system used by the FCC for new licenses, renewals, upgrades and modifications. I am not a subject matter expert nor have I used the system to renew yet. I am a Volunteer Examiner and regularly see/hear the system explained to exam candidates and I also have helped my XYL navigate through the system for her license. 
First, there are two parts to the system CORES and ULS. Simply, CORES is the part that takes your money, ULS is the part that handle the management of your license. Both are US Government web sites and do not have easy graphic user interfaces. To add to the complexity, there was an older version of CORES which became outdated on JULY 15 when the newer version came on line. As far as I can tell, information from the OLD system did not migrate to the new, hence the notices to go create a new user name and password prior this past July 15. If you did not do so, you will need to go to the NEW system and register plus create a user name and password. You can check availability for each on the web page for the new CORES. Here is the link for that:

https://apps.fcc.gov/cores/userLogin.do

One MUST HAVE piece of information is a current, working e-mail address! Also, keep in mind info does not migrate from CORES to ULS so just because you have it in one does not mean it is in the other. Tracking? 
Ok, if you have CORES registered and your user name/password work, then let's proceed to the ULS (Universal Licensing System). Here is the URL for the Universal Licensing System:

https://www.fcc.gov/wireless/universal-licensing-system

Here are the instruction straight from the FCC page:

Renew your license through the Universal Licensing System (ULS) at any time within 90 days of the expiration date for the license and up to two years after the license expires.

To renew, go to the ULS Home, select Online Filing, and follow the instructions below.

1. Login to the ULS License Manager with your FCC Registration Number (FRN).
2. From your License At A Glance page, choose the Renew link in the right hand menu called Work on this License. When your license is within the renewal period of 90 days before the expiration date until the expiration date, or within the 2 year grace period allowed there after the Renew link will appear. If your license is not eligible for renewal the link will not appear.
3. On the Select Updates page, review the licensee information displayed beneath the table of license information. If any of the data is missing or out of date you must update it. Click on the box to the left of the Licensee Information heading to insert a checkbox and select it.
4. When ready click Continue.
5. Answer the questions on the Applicant Questions page, and click Continue when ready.
6. On the Licensee Information page, review and update all of your licensee information. Make any corrections that are necessary.
7. On the Summary page review the information you have entered. If you wish to make additional changes, click the Edit button next to the section of your application you wish to Edit. You will be able to return to that page of the application. Make the desired change and select the Return to Summary button.
8. When ready to submit your update to the Commission, choose the Continue to Certify button.
9. After reading the certification, enter your first and last names in the boxes at the bottom of the page. You MUST sign the application. When finished choose the Submit Application button.
10. From the ULS Confirmation screen, we recommend you print a copy of your application and/or the Confirmation screen itself from your web browser.

Note: The address and contact information you have entered in CORES registration will not be automatically associated with your licenses. To change the address or other contact information on your license, you must update your information in ULS.

(Joe again here): When your renewal is ready to be processed, you will receive an email containing a link for you to pay the $35 fee. DO NOT use a smart phone to pay the fee, use a regular laptop or PC. There have been reports of issues with people using smart phones to pay the fee, so avoid that. 
Ok, I hope this helps, I'm sorry if it's complex, but I didn't create it and don't necessarily endorse it, it just "is what it is!" 
To summarize, if you haven't registered in the NEW CORES system, you need to. If you are within 90 days of expiration, you can renew by registering in CORES and then going to the ULS and following the instructions above. 
Thanks and Good Luck! 
73,
Joe
AA5AD