There are several materials that are commonly used for cushion covers, each with their own advantages and disadvantages. Here are some of the most popular materials:

1. Cotton: Cotton is a popular choice for cushion covers as it is breathable, soft, and easy to care for. It is also available in a wide variety of colors and patterns.
2. Linen: Linen is a durable and natural fabric that is highly breathable and has a textured, slightly rough feel. It is great for warm climates as it keeps you cool.
3. Polyester: Polyester is a synthetic material that is durable and easy to care for. It is resistant to stains and wrinkles and can be a good choice for cushion covers that are used frequently.
4. Velvet: Velvet is a luxurious and soft fabric that adds a touch of elegance to any room. It is durable and can hold up well over time.
5. Silk: Silk is a delicate and luxurious fabric that is soft and smooth to the touch. It adds a touch of sophistication to any room but requires special care and is not very durable.
6. Wool: Wool is a warm and cozy fabric that is great for cushion covers used in cold climates. It is durable and has natural stain resistance but can be scratchy to the skin.

Ultimately, the best material for your cushion cover will depend on your individual needs and preferences. It is important to consider factors such as durability, ease of care, and the overall look and feel you are going for when selecting the material for your cushion cover.