As mentioned, in a regulated market, unlike in a liberalized market, the activity of the various natural gas suppliers is completely subject to the rules established by the entity. Companies that practice regulated tariffs are so-called retailers of last resort (CUR).

EDP ​​is the number one resource that provides a web page so that its customers can switch to the regulated market.

EDP: Transforming to a Regulated Market in Just 5 Steps
The EDP Gateway to the Regulated Gas Market is now available online.  To do this, customers only need Fill out a membership application form.  On the portal you can read ...

According to Decree-Law No. 57-B / 2022, published on September 6, 2022, it is currently possible for families and small businesses with annual consumption less than or equal to 10,000 cubic meters to contract for free.  Supply of natural gas in the regulated market.  As for the remaining customers whose annual consumption exceeds 10,000 cubic meters, they are not covered by the decree-law.

If your CUI does not start with "PT1601", you should contact the latest product vendor (CUR) in your area.

It should be noted that the possibility of returning to the organized market was one of the measures proposed by the government to confront the increases in customs duties scheduled for next October.
Remember that until 2012, all domestic customers had a regulated tariff for electricity and gas.  With the advent of the free market, many Portuguese moved in order to obtain lower tariffs.  Those who have not signed any contract will remain in the regulated market.  Whoever does it will be in the so called liberated tariff and this can be seen in the invoice.
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