Audi A4 2018 Bulb Size
Bulb size chart
This 2018 Audi A4 bulb size page is designed to help you verify the correct bulbs by lighting position, so you can replace the right lamp without guessing. Because Audi used different lighting packages and trim combinations, the exact bulb setup can vary by market and body style, but this page organizes the common exterior and interior locations in one place.
Use it as a quick reference for items like the headlights, tail lights, brake lights, license plate lights, turn signals, and cabin lights on the 2018 Audi A4. Whether you are replacing a single burned-out bulb or planning a full lighting refresh, checking by position makes it easier to match the correct fitment before you buy.
For the best fit, always compare the bulb chart with your specific A4’s trim and lighting package, since halogen, HID, and LED-equipped cars may use different parts in the same location. This is especially important on aftermarket conversions, where a previous owner may have changed the headlight setup or interior lamps. If you are unsure, inspect the installed bulb before ordering and confirm the connector style, base type, and housing design so you do not end up with the wrong replacement.
FAQ
What bulbs does the 2018 Audi A4 use for the headlights with LED headlights?
On 2018 Audi A4 models equipped with LED headlights, the high beam and low beam bulbs are listed as LED. The front turn signal bulb is also listed separately for LED headlight vehicles.
What headlight bulb is used on the 2018 Audi A4 with HID headlights?
For A4 models with HID headlights, the headlight bulb for both high beam and low beam is D5S. The front turn signal bulb for HID headlight vehicles is listed as 64132.
Are the brake lights on the 2018 Audi A4 LED?
Yes. The brake light bulb is listed as LED on this page for the 2018 Audi A4.
What is the license plate light bulb size for a 2018 Audi A4?
The license plate light bulb is listed as LED. That means the assembly uses an LED light source rather than a traditional replaceable incandescent bulb in the charted setup.
Does the 2018 Audi A4 use LED bulbs for the tail lights and parking lights?
Yes. The tail light bulb and parking light bulb are both listed as LED for the 2018 Audi A4.
What bulb is used for the glove box light on the 2018 Audi A4?
The glove box light bulb is listed as 2821.
Are the interior dome, map, vanity mirror, and door lights LED on the 2018 Audi A4?
Yes. The dome light, map light, vanity mirror light, and interior door light are all listed as LED on this page.
What is the front turn signal bulb on a 2018 Audi A4 with LED headlights?
For A4 models with LED headlights, the front turn signal bulb is listed as LED.
What is the front turn signal bulb on a 2018 Audi A4 with HID headlights?
For A4 models with HID headlights, the front turn signal bulb is listed as 64132.
Does the 2018 Audi A4 have different bulb listings for trim or market differences?
Yes. Trim and lighting package can vary by market and body style, so some bulb positions may differ depending on the exact vehicle configuration.
What should I check before buying replacement bulbs for my 2018 Audi A4?
Check the installed bulb or the original housing first, then confirm the lighting position, connector, and whether your car has LED, HID, or another lighting package. That is the safest way to avoid ordering the wrong part.
Can I use this page to replace rear turn signal, reverse, and side marker bulbs on the 2018 Audi A4?
Yes. The page includes the rear turn signal bulb, back up reverse light bulb, side marker light bulb front, and side marker light bulb rear, making it easier to match each position to the correct fitment.