Visitors to West Mercia Police's Twitter page were advised to report any "non urgent" crimes online in a tweet sent on at 5.17pm.
"Our neighbouring police forces will be absorbing our telephony demand so you can still reach us in case of emergency by dialling 999," said the tweet.
It said the "outage" was due to technical issues with the 101 and 999 system.
The force directed people to "use our simple, confidential online service to report any crime you've been a victim of or witnessed: from assault, theft or criminal damage to harassment, online abuse or blackmail."
The force added that any immediate urgent need should still use the 999 system.
It wasn't until 8.45am on Tuesday that the force confirmed that its phone lines were up and running again.
The Shropshire Star only last week reported that a “system outage” left West Mercia Police “unable to accept 999 and 101 calls” and relying on an external backup network just over a month ago.
At a meeting last Tuesday, Police and Crime Panel chairman Aled Luckman asked how such a failure was “physically possible in this day and age” and why the force did not have an internal backup.
Police and Crime Commissioner John Campion said he could not go into detail about the July 23 outage, though he said incidents like that happen “more often than you would perhaps think” but there was a “well-practiced” procedure to deal with them based on “mutual aid” between forces.
Mr Campion said he could “not go into details, as you would expect” but said he had been reassured about what had happened and that the force’s contingencies and mitigation measures worked well.
“The ‘nines’ system is based on mutual aid,” he said.
“There is always going to be the possibility of failure when it comes to technology. We, of course, can improve, absolutely, but I am assured the right things happened when the failure happened.”
He added that it was important “the demand we face is managed appropriately”, and there was still a lot of “inappropriate contact” on the emergency and non-emergency lines.
He said the force would have to engage with the public about how to use them, and when to use online reporting methods.
On Saturday the force tweeted: "We are receiving high call volumes - so sorry for keeping you waiting - if its not urgent consider going online - we have lots of helpful advice on there and you can report incidents and crimes."