Line Umpire

Guidance for Line Officials

The following guidance is also available as a PDF single sheet in the Files Section below.

Be neatly dressed in the appropriate USTA uniform, unless issued another uniform by the tournament.   Arrive early (perhaps 7 minutes) to your assigned court and be prepared (with hat, sunglasses, water bottle, etc.) to go on court.

Long Line:

·         Before each point move quickly to your appropriate position depending on the crew configuration

·         Ready Position (RP): feet roughly shoulder width apart, hands on knees (similar to a baseball umpire)

·         At Ease: feet roughly shoulder width, hands clasped behind back

·         If the server is on your end, watch server until the toss starts, then move your head and eyes to the line

·         Head movement (HM) during the point is important. Follow play then go to the line when threatened.

·         Signals: Safe signal (SS) - given on a ball 18" or nearer, hands together, just off the knees. Signal Out (SO) - from the ready position, shoulder high, straight with thumb in, after a loud, crisp "out" call

·         Moving from center to side line requires quick movement. Use a one-handed running safe sign (RS). Be sure to keep an eye on the action as you move

·         When calling the serve behind the receiver, there are 3 acceptable positions: 

1) on the line, in the RP or crouched low. 

2) inside standing (hands on thighs) or in the RP

3) outside standing (hands on thighs) or in the RP. After the serve, move quickly to the normal RP

Base Line:

·         Chair should be angled/canted toward the intersection of the serve line and the far sideline

·         Sit alertly with good posture, hands resting on knees, feet flat on the ground

·         If the server is on the opposite end, you have no call to make until at least 3 hits. So watch the point develop.

·         If the server is on your end, watch for foot faults, but do not "hawk" the line. It is important to watch the point develop. Head movement (HM) is important - do not track or stare at other end of the court. Rather follow the ball in play (at least from service line to service line) and go to your baseline when threatened. The decision to go to the line should be made before or as the ball crosses the net, giving time to decide on a focal point for looking at the line depending on the direction the ball is traveling.

·         If you are on the same side as the Chair Umpire (CU). SS's (within 18") and SOs should be slanted toward the CU. If opposite the CU, hand signals should be just off the knees (SS), or straight from the shoulder (SO).

Service Line:

·         Chair should be facing straight down the service line

·         Sit alertly in a comfortable position, hands resting on your knees, feet on the ground

·         When the server starts to toss the ball, move your head and eyes to the line

·         When you are on the same side as the Chair Umpire, SSs and SOs should be slanted toward the CU. If opposite the CU, hand signals should be just off the knees (SS), or straight from the shoulder (SO)

·         If the serve is out, loudly call "fault" and then make your SO. Your arm should be straight from the shoulder, thumb closed against your hand.

·         Additional duties: have a measuring device to check net between sets and prepare for ball change if needed (2 or 3 games before change, be sure and shake the balls, check for pressure and visually check for defects)

Crew Chief:

·         If requested, assist chair umpire with pre-match court preparation. Be sure court is clean and chairs for line umpires are properly placed in relation to the sun especially for baseline and serve

·         Towels, if any, in place on chairs

·         Be sure all crew members have arrived, know their positions, and are ready to work


·         Look to the chair umpire 

(1) on point ending shots, 

(2) between points, 

(3) and always on changeovers

·         Don't dive, flag, or embellish hand signals. Just off the knees (SS), or shoulder high and straight (SO)

·         Signals with bent arms are not proper technique

·         "Out" calls should be crisp, prompt and loud. Prolonged "out" calls do not necessarily sell.

·         Always follow the Official's Code of Conduct, on and off the court.


Subpages (1): Line Umpire Grading
Allan Thompson,
Mar 7, 2013, 10:03 AM