The short and simple answer is, yes, blast emails can be spam. However, that doesn’t mean they are if you use them in the right context. Sending email blasts weekly, or even every few weeks, may risk your emails crossing the line and falling into spam territory. That’s because spam is usually unsolicited and irrelevant, which your blast emails could be if sent too often. But, if you send an email blast every now and then that is relevant to the majority of your customers, then it’s unlikely to be considered spam.
So long as you send blast emails in accordance with customers’ permissions, they’re relevant, have a clear way for recipients to opt-out and are compliant with compliance regulations, then you should have nothing to worry about.

What are the pros and cons of email blasts?
As with any marketing strategy, email blasts come with pros and cons.