Technically, there is no way to set up an annual subscription. But I believe that you can get around this: request a down payment for the entire first year, and then a monthly-periodic discount.
For example, suppose you offer a monthly plan worth $ 100. And you want to offer an annual plan of $ 900 (25% discount). Instead, you can offer a down payment of $ 900, followed by 36 monthly monthly payments of $ 75.
What this means for your business is that as soon as the user has paid and used your service for a whole year, you begin to treat it as a “loyal customer” and allow it to pay a discount without any obligations for the next of the year.
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