[at-fates-hands]

>> First, you could send an email to existing customers telling them that you are raising prices but that you are grandfathering them in and their rate won't change.

This is the approach I took, but worded similar to how cable companies word their advertising - that the discount is only valid for x amount of months. After that period, they could be subject to a "change" in price. The wording is left vague so you don't say there will be an increase, simply that the rate could change after their discount expires.

This was usually after a 12-24 month period. After two years of discounts, I finally increased the monthly fee, but only by about 8% which still left them paying less than new customers - which is an important point. Yes, they're paying more than they did, but it's still less than new subscribers, giving them the impression they're still paying less - when in reality, I'm just making back the discount I was giving them.