Yes, in most cases you can use LED light bulbs in your existing fixtures. LED bulbs are designed to be compatible with standard light fixtures that use traditional incandescent or CFL bulbs, which means they can easily be interchangeable. However, it is important to check the specifications of the specific LED bulb to ensure it is suitable for your fixture. Some older dimmer switches may not be compatible with LED bulbs, which can lead to flickering or reduced performance. If you plan to install LEDs in a fixture that is on a dimming circuit, it is advisable to look for LED bulbs specifically marked as dimmable. Additionally, when replacing bulbs, make sure to match the wattage requirements of the fixture and choose a suitable base type. eLightbulbs.com offers a wide variety of LED options that cater to different types of fixtures. For more detailed information on a particular bulb or fixture compatibility, it may be helpful to refer to the current web page.