The least expensive deck railing is a simple wood railing. However, a simple wood railing may not be as sturdy or safe as other types of railings, so it is important to consider your needs before selecting a type of railing. Metal railings are generally more expensive than wood railings, but they are more sturdy and can be more aesthetically pleasing. If you live in a region that experiences severe weather conditions, such as high winds or heavy snowfall, you may want to consider investing in a metal railing.

The least expensive deck railing is a simple wooden rail. You can buy the lumber and hardware at a home improvement store, and build it yourself for around $50. If you don't want to build it yourself, you can hire a contractor to do it for around $100.