My iPhone iCloud backup is taking hours. What is the problem?

My suggestion would be to skip iCloud Backup all together by backing up the 6 to a computer and restore that backup to the 8. I'm fighting a nasty battle trying to restore to an iPhone X where iCloud Backup lost years worth of photos from my previous phone (7 Plus), even though iCloud Backup said everything was backed up successfully. Apple support's response was, albeit very polite, "sorry, we can't help you."

CosmoKitty wrote:

Thank you for your reply, Tim. I bought an 8+ and my backup phone data won’t transfer from my old 6. I am currently operating w/ 2014 texts etc. It’s nuts! I have always backed up my iPhone to my computer, however, on my 6 it’s telling me that I have not backed up in 164 weeks to the cloud! I have roughly 33gb to backup out of 64gb. My WiFi usually isn’t too slow, as it’s dsl, but it’s been a frustrating 2 days. If you have any other advice LMK. I’ve got my apps up to date on the 8+ now, but the texts and lack of contacts since 2014 is blowing my mind! It also won’t pick up my Fitbit via Bluetooth. Thanks again in advance!

It will take a long time to backup to the cloud if you haven't done so in a long time. I've had two user who had to take their phone home to finish the backup, because it was taking a long time. Advice them to plug it to a wall outlet and locked the phone and let it finish the backup, preferable before they go to sleep.

The next day I was able to use that backup to their new phone without any data loss.

One user who updated their phone was able to backup to icloud quickly because he does it often.

CosmoKitty wrote:

Thank you. I’ve had them plugged in since 11am and the 8+ says it will be at least another 3 hours. Crazy, no?! Question, my 6 is what has all my information and recent texts. Should I bother even trying to back up the 8+ too? Again, I’ve had both plugged in since 11 AM.

No not crazy, not sure where your located, so that would be 4 hours pacific time. ARe you backing up your iPhone 6, so you can use that backup on your new phone?

if you leave it plugged in and locked and leave it alone the process with go faster.

It's big and your WiFi is slow?

You haven't provided enough information for anyone to assist in troubleshooting anything.