Several major banks make it possible to combine points across multiple cardholder accounts. This is a huge benefit to get the most out of your points! For example, Chase allows you to combine points from no-annual-fee "cash back" cards like the Chase Freedom Flex® and Chase Ink Business Cash® Credit Card with transferrable points cards like the Chase Sapphire Preferred® Card. By doing this, you can take advantage of huge welcome offers - without paying an additional annual fee!
Related guide: Transfer Partners by Bank