Suggestions for "spread the word, get free months"?

There are two halves to my market: healthcare professionals and their patients.

The professionals are an evergreen referral source.
I"m thinking of giving the professionals a free month. And, if the number of active professionals gets to 10, then everyone gets a second month. Thereafter every time it doubles, I add a free month.

I can track that with the URL that gives them the free subscription.

Any thoughts on how else to maximize this?

I’ll be sending out special emails (and offers for tours, etc.) to those free Pro subscribers.
I’ll also let them know the best places to share their link.
I’m considering including their email address in the referrer ( ?utm_campaign=MyEmail@name.com) so I can find the folks who refer a lot.

Maybe offering some sort of intrinsic prize for the biggest referrer:

  • Extra months
  • Free personalized Tour
    -Subscription to our other software.

For healthcare, I’d hesitate to give professionals a free month in exchange for a referral, as that can be seen as “buying” them.

Isn’t it possible to give the professionals a limited, unconditional free account, where they can treat one patient? (they’d have to pay for treating multiple patients). If they like, they refer it.

And why don’t you give the professionals a free voucher/flyer (on paper), they can give to their patients with a code to track the professionals (and an offer for new customers).

  1. The referral is only for other therapists. So I don’t think that would be an issue. (And I do agree, and would not give professionals anything in exchange even for getting patients to even try it)
  2. We will be giving those professionals a seperate voucher for a free trial for patients. But the bigger issue is reaching professionals to begin with.
  3. There’s no simple way (currently) to give them a free account for one patient.