There are many choices of plants that will do nicely in the same growing conditions where Hostas prosper. Most enjoy some sunshine early and late in the day and broken sun or light shade during mid-day. They, like Hostas, prefer well-prepared soil with some organic matter added, a little balanced fertilizer, and regular watering. Some of my favorite companion plants for Hostas are:
A few blooming tulips are nice in the spring with the newly emerging Hostas.
Spanish Bluebells bloom for an extended period.
There are numerous Heucheras in many colors that complement.
Corydalis lutea with Hosta 'Orange Marmalade.' Corydalis lutea is a willing little plant that can spread around the garden.
Brunnera is special when it is in bloom and also nice afterward.
Tulips and European Ginger
Hakonechloa, Impatiens, Ostrich Ferns
Hostas and Japanese Maples make a gorgeous pairing.
Sweet Woodruff with Hostas 'Wolverine' and 'Golden Tiara'