If you maintain a clean list, with subscribers who have opted-in to receive your newsletter and are currently anticipating your campaigns, that you shouldn't have any fear of having your email marketing efforts marked as spam.
Nonetheless, it's worth keeping in mind that there are two points that bear consideration, as both play a major role and can influence whether your campaigns end up on the junk, bulk, or spam folders of your recipients email service.
The two factors you should keep in mind are:
A. Sender Reputation
Moosend is a hosted solution, which means that the campaigns you send out to your recipients are sent out using our own mail servers. A recipient's email client (e.g. Gmail, YahooMail, Outlook, etc) will review the sender address of your campaign, among other things, when deciding whether to accept or reject the email.
For this reason it is important that you take advantage of the SPF and DKIM frameworks, with which Moosend is fully compliant, as they boost your sending reputation by letting the recipient's email client know that you are sending your campaigns using our servers.
We have amazing server reputation and excellent deliverability rates, so make sure that you set up SPF and DKIM and take advantage of it!
B. Message Content
Once your newsletters pass through the scrutiny of your recipient's email client (e.g. Gmail, Yahoo, Outlook, etc.), their content will still need to be subjected to special analyzing filters which help determine where your messages ought to be be placed - the inbox is not the only option for these filters, but that's what you should be aiming for!
Available filters, such as SpamAssassin, are typical. For this purpose, Moosend provides a content analyzer so that you can test how your newsletter fares against filters.
SpamAssassin by no means the only available filter, there are quite a few proprietary ones, but they all have a common purpose: to prevent spammers from reaching inboxes. And that's what you should too! Getting your recipient's attention is important and you don't want to end up inside a clutter of unsolicited emails. So make sure your content is relevant to what your subscribers expect.