When it comes to subscription based sites there are a whole host of things that you can do to increase the length of time that someone remains subscribed. Most of these can be developed or added in over time but one strategy works best when you first launch and that is the concept of grandfathered pricing.
What is Grandfathered Pricing?
When launching any subscription site it's not uncommon to offer a discount or trial offer to your new members. Often your site isn't as full as it will be one day, the community is just forming and coming together and it can help people to make the jump and become members of an unproven site. However one way you can build retention into your launch is by setting a low price for your first members during your launch period and locking them into that price for the lifetime of the site.
With grandfathered pricing, if you increase the subscription price of your site in the future your first customers still only ever pay the same subscription level that you offered during your launch. This is powerful because it acts as an incentive to sign up during your launch to get the discount and creates a genuine urgency deadline for members to register before the offer closes. But it also means that when a member signs up to your site they are far less likely to leave it as they risk losing the discount even if they decide to register again at a later date.
If your site is running Wishlist Member then setting up grandfathered pricing is a simple process as the subscription price is somewhat detached from the subscription levels with most payment processors so all you need to do is set the lower price as normal during your launch. After your launch period is over just raise the price on your payment button for future members and all your existing members will continue to pay the subscription price that they set up their contract with. This is also true for most membership solutions that integrate with PayPal.