Several people immediately took to social media sites in the Algarve to question what had happened.
People from Albufeira to Portimão said they had felt the quake.
According to the IPMA site, the epicentre was located in Silves, and the tremor is one of the biggest to be recorded in Portugal in recent months.
There were no reports of injuries or structural damage.
I live near Silves and so am used to tremours. I was sitting down for lunch when my husband and I heard it coming. There's a quake, we said and put our feet on the ground to feel it. I felt the tremour on my side but my husband felt nothing.
By Glenis from Algarve on 01 Feb 2019, 06:32
We heard and felt the quake quite loud and strong just thought it was a delivery of huge rocks next door!
By Samantha Wright from Algarve on 01 Feb 2019, 06:56