Today most businesses have a website, email list or maybe even an app. This is an opportunity to use your printed envelopes (or other printed items) to promote these digital channels. You may send out invoices to customers that have never used your website so why not remind them on every invoice, statement, and envelope you send them. Not all your customers may be on your email mailing lists. Print coupon codes on your envelopes to push the customer to use your website. Ask your customers to subscribe to your newsletter either digital or printed. Your envelopes are great ways to keep informing your customers and encouraging them to use these other digital services you provide. Always share your website address and other digital services on your printed envelopes. This is as important as your physical address.