A Cellphone Tower

Is your phone not holding calls where it previously had a strong signal?  If you have a CDMA device like those found on Sprint and Verizon, you may need to update your Preferred Roaming List (PRL).

The PRL is a list that allows your phone to roam off of towers that are not part of your native network, such as a sprint phone connecting to a former Alltel tower if none of its own are available.  Because roaming agreements are constantly changing and new towers are added all the time, it's important to keep this list up to date.

For most CDMA carriers (including Verizon), you can update your PRL by dialing *228 and selecting the appropriate option.  For example, on a Verizon phone you dial *228 and then select option 2 and listen to the horrible programming music while your phone downloads the latest PRL.

For Sprint, there are two options.  The first is to contact Sprint Customer Service and get your account approved for an update and then dial *2 and follow the instructions.  If you have an Android device, you can also check your PRL by tapping Home > Menu > Settings > System updates > Update PRL. (Thanks milominderbinder) 

With Verizon prepping its LTE launch and Sprint lighting up new WIMAX markets, both carriers are spending a lot of time and resources ensuring their current 3G networks are optimized.  This means a lot of adjustments to which towers cover a specific location, as well as the addition of new towers to handle additional traffic.  Because of this, it's a good idea to update your PRL at least once a month so your phone will always have access to the best coverage available in your area. [Via Android Central Forums]

 
There are 26 comments

andyp714 says:

So how do we do it on the droid x kind of hard for me to understand

horseshoe says:

On the Droid X you will find the PRL listing at the bottom of the list once you look at the About Phone listing on settings. Dial that *228 and choose option 2 for the PRL update.

horseshoe says:

If PRL is for cell signal coverage, why does the Droid X have issues with losing 3G to 1X and back again? This issue is pretty heavily commented on at the Motorola site but no solution has arrived. PRL is important but the other issue has become an issue.
Anyone?

andyp714 says:

O thx man I was trying to update on phone itself lol..ya I have that same problem as well

icebike says:

It seems rather odd users would have to do this at all.
Shouldn't this be something the carrier does each time you boot the phone?

Menno says:

When you boot your phone it updates native coverage. The PRL has to be manually updated. Edit: I should also mention that most people never (or rarely) shut down their phone. Updating the PRL forces the phone to update it's native tower configuration as well as the PRL itself.

icebike says:

I suspect you are right about most people never shutting it off, but I wager fewer people ever heard about updating their PRL.

Can't the carriers send commands to the phones to do this?

I've never owned a CDMA phone so pardon my cluelessness.

Menno says:

Yeah, it's a bit different with CDMA phones. I'm not a tower tech, so I can't go into exactly why, but for whatever reason, they require action on the part of the user to update the PRL

Just completed an update and didn't see much difference in my Fascinate. However, I live in a rural area so tower tweaking probably didn't occur.

Njphenom says:

I updated the prl on my epic but nothing changed. I got excited too cause I thought I was gonna be able to get more than on bar inside my house. And I get at least five bars everywhere except for my house and that sucks

Menno says:

I guess I should've added that the PRL update isn't a magic fix. It's mainly for people who used to have GREAT reception in a given area and now it sucks, or if you traveled several hundred miles away and your phone can't seem to hold onto a signal while others can. Indoor reception is something that can't be fixed by PRL updates sadly. Buildings hate cellphone signal, some more than others. Outside I get full bars and pretty fast 3g, sitting in my room, 3g becomes a maybe. :/

arnmsctt says:

Dialing *22899 on Verizon will skip the command prompts and go straight to the horrible programming music.

Menno says:

*22899 will actually bypass and select option1 which programs your phone. This also typically updates the PRL, but if you have any sort of password lock on your phone it can reset it. Bypassing the programming menu like this can also make phones do some weird things. Android phones seem to be fine, but it used to make blackberry's lose all data connectivity until you resent the host routing table and programmed the phone using the correct menu options. Not every time, but it has happened.

arnmsctt says:

Good to know. Thanks for the extra info.

I thought *22899 was for aircards and would mess up data with most phones. Maybe it was only BB then?

domeboy says:

Horrible music??? I can't believe people are dissing the music I picked as my ringtone. I am still hoping to buy the CD.

For verizion I do *22891 which updates prl and re-programs it also. And it skips command prompts also!

6s1d9 says:

Not to sound all 'know it all'ish' bit the *228 thing is old news. Been doing it for years to ensure I'm all up to date... although I did find the Verizon rep a little pushy when I changed my plan and she said "you HAVE to update your roaming capabilities by pressing *228 bla bla bla"

chief113 says:

I wonder why the verizon reps didn't tell me that before I left their horrible service to come back to att. Oh well..

davidnc says:

..also *18 will connect you to the newest tower from whereever you are at that particular moment in time , its just a 2 second popup window once you dial *18 you dont hear any kind of recording or anything you just see a 2 second pop up window that goes away on its own.

mike340t says:

Actually for my Epic it's: Home > Menu > Settings > About Phone > System Updates > Update PRL.

Paladin says:

Doing the Home > Menu > Settings > System updates > Update PRL.
on my Evo just made it stuck trying to update the list. I had to reboot to make it go away.

josepht84 says:

After doing a Verizon PRL update on my 2.2 Incredible, my Android Market will not update or download apps. I've tried clearing the cache and data of the download manager and market with no success. Anybody else experiencing this?

*Nevermind seems the Android Market is down. Just bad timing on my part.

Sublym1 says:

Just performed the PRL update on my Fascinate. Was getting 1-2 bars on the norm in & around my house. Now it's stays steady @ 3 bars. Haven't checked yet on how good my 3G signal is since I connect via Wi-Fi @ home. Thanks!

for LG Optimus the sequence is Home > Menu > Settings > About Phone > Update PRL

joquinn1289 says:

I have a sprint samsung phone but has been flashed for pageplus. I let my phone get cut off and just got a card to turn it back nd wheni I did it started saying preferred system and going into roaming when I should have a full signal and no roaming in my area how can I fix it? Do I need to have it flashed again? Or is there something else I can do myselff because I can't get it turned on until I fix the problem.