I have been granted a Swedish residence permit. In the application, I requested that the first day of validity be (for example) 10 April 2025. The card has been printed and delivered to me.
The front of the card looks very similar to the specimen shown here: https://www.migrationsverket.se/en/word-explanations/residence-permit-cards.html. In particular it has my date of birth and the date of expiry of the permit, but no other dates.
On the back of the card the only information is the place of issue, and one date, labeled 'date of issue'. This is (for example) 10 March 2025.
On the webpage linked above, it is stated:
The residence permit card is produced in connection with the decision to grant you a residence permit, but no more than six weeks before your permit will begin to apply.
Or in Swedish:
Uppehållstillståndskortet tillverkas i samband med att beslutet fattas, men tidigast sex veckor innan uppehållstillståndet börjar gälla.
On what date does the permit become valid for travel? That is, on what date can I enter Sweden on this permit? Or, in plain language: on what date may I move to Sweden?
Edited to add: The information letter that arrived with my permit states
You cannot use the card to travel to Sweden or the Schengen area before the validity period of your residence permit has started. This information is contained in your decision.
In Swedish,
Du kan inte använda det till att resa in i Sverige eller Schengengenområdet innan tiden för ditt uppehållstillstånd börjar gälla. Datumet för när ditt uppehållstillstånd börjar gälla finner du på ditt beslut.
The original email informing me of the decision states
If you live outside Sweden, and want to get your complete decision, you can contact the Swedish embassy or consulate general as you specified in your application. ... Notification of the complete decision is made only if you visit the embassy or consulate general.
That is,
Bor du utanför Sverige, och vill ta del av ditt fullständiga beslut kan du kontakta den svenska ambassad eller generalkonsulat som du specificerat i din ansökan. ... Underrättelse av hela beslutet görs endast om du besöker ambassaden eller generalkonsulatet.
There is some reason to think that some of this text may be out of date and should be refreshed now that the residence permit has a new format - the information letter talks about a date of validity on the front of the card, which is no longer the case. Nonetheless, the official answer appears to be that I must specifically ask for this information in person at the embassy!