You're a startup, non-profit, charitable or educational establishment wishing to use Heroku at a discount.
Presently, Heroku does not have any discount offerings, even for non-profit or educational projects. However we do already offer discounts with the many free add-ons available on our Add-on Marketplace.
You may also be interested to know that our parent company does have a formal discount program for non-profits through the Salesforce Foundation.
Additionally, if you're a non-profit or an educational organization, be sure to view our article collection on taxes and tax exemption. We encourage you to interact with our Support Team in order to request your account be marked for tax exemption.