I'm looking for shapefiles of the Portugal post codes 4 digits.
Any open source or fee source that will have this info?
I agree you are best asking this on the Open Data stack exchange. But there is this great search tool called Google, type anything like "free portugal postcode data" and first thing it throws up is this:
Note it is out of date as it appears to be fixed at 2012, but it links through to the original source of the data.