Hello Yhowe,
Welcome to the community!
Well, it depends on what free gift you refer. There has been a $50 gift text message which has been going around (see here). As noted in that thread, that message is most definitely a SCAM / SPAM.
On the other hand, many customers have received offers for free data (see here). I believe those messages to be legitimate. I can state that some customers have legitmately received free bonus data in the past (see here, here, and here, etc). In addition, there have been some relatively recent articles noting Fido offering bonus data to some customers as well (see here and here).
A couple of tell-tale signs the the message is SPAM. Firstly, Fido won't send e-transfers via email or text message link. Fido will automatically credit your account.
In addition, if Fido does send legitimate SMS, it will come from one of their short codes, not a phone number. As far as I am aware, many of their promotions come from 4745 or 4735 (see here and here). Admittedly, since spoofing is so wide-spread, it's possible the spammers/scammers could eventually learn to spoof those codes as well.
Another sign is Fido's recent adoption of the a URL shortening service. I believe it's Bit.ly (see here). As far as I am aware, the links would be for the Fido.ca domain.
Hope this helps 😀
Cheers
