If you’re looking at a tennis court and wondering what the narrow strips along each side are for, those are the doubles alleys. They add width for doubles rallies, but they do not count as part of the court in singles. The tricky part is that the alleys are out of bounds for every serve, even in doubles.
Knowing when the alley is in play makes line calls easier and opens up useful tactics. Here’s how to spot the alleys, understand their dimensions, and use them wisely in a match.
What Are the Tennis Court Alleys?
The tennis court alleys are the long, narrow strips between the singles sidelines and the doubles sidelines. There is one alley on each side of the court. They are sometimes called doubles alleys because they extend the playable width of the court for doubles.
A regulation court is 78 feet long. Its width depends on the format:
| Court area | Width | Alley included? |
|---|---|---|
| Singles court | 27 feet | No |
| Doubles court | 36 feet | Yes |
| Each doubles alley | 4.5 feet | Included in doubles rallies |
The alleys run parallel to the sidelines, from the net to the baselines. They do not include extra space behind the baseline or beyond the net. Lines count as part of the area they mark, so a ball that touches the doubles sideline is in during a doubles rally.
When Are the Alleys In or Out?
In a singles rally, the court is bounded by the singles sidelines. A ball landing in either alley is out. In a doubles rally, the court includes both alleys, so a ball landing there is in.
Serves are the exception that catches many new players. Whether you are playing singles or doubles, a legal serve must land in the correct diagonal service box. That box is inside the singles sidelines, so the alley is out for the serve. A serve that lands in the alley is a fault.
Once the serve is returned, the doubles sidelines apply in doubles: the alleys become fair territory. In singles, the narrower singles sidelines remain the boundaries for the whole point.
How to Find the Alleys on a Court
Look for the long inside line nearest the middle of the court and the long outside line near the fence. The strip between them is the alley. The inner line is the singles sideline; the outer line is the doubles sideline.
On a court marked for both formats, the lines can look busy at first. Follow the sidelines from the net toward the baseline: the singles boundary sits inside, while the doubles boundary sits farther out. If you’re unsure during a casual match, agree before play on which format you’re using and call balls based on that court’s sidelines.
Remember that painted lines are in. If the ball touches even the edge of the relevant sideline, it is good. A ball that lands fully outside the line is out.
Why the Alleys Matter Tactically
The alleys change the angles and distances players have to cover. In doubles, a deep shot into the alley can pull a player away from the middle, while a sharp crosscourt angle can create room for a partner to intercept the next ball. Good teams also use the alleys to stretch opponents before aiming at the open space.
That extra width comes with risk. Aiming close to the doubles sideline leaves less margin for error, especially when you’re moving or hitting under pressure. A safer pattern is to target a few feet inside the line, then go wider when you have time and balance.
In singles, the alley is a tempting target but usually a demanding one. A player may use a wide crosscourt shot to move an opponent off the court, then hit behind them or approach the net. The goal is often to make the opponent run, not to land every ball right on the boundary. Aiming too close to the alley can turn a strong attacking shot into an unforced error.
Common Alley Mistakes
- Playing an alley serve: The doubles alley is still out on serves. Aim inside the singles sideline and into the correct diagonal service box.
- Using the wrong sideline for the format: The singles sideline governs singles points; the doubles sideline governs doubles rallies.
- Calling a line ball out: If the ball touches the line that marks the court boundary, it is in.
- Overusing the alley as a target: Aiming for the very edge can create needless errors. Build the point with safer targets before going for a sharp angle.
Frequently Asked Questions
Are tennis alleys part of the court?
They are part of the court during doubles rallies. In singles, a ball landing in an alley is out. For both formats, the alleys are out of bounds on serves.
How wide is a tennis court alley?
Each doubles alley is 4.5 feet wide. The full doubles court is 36 feet across, compared with 27 feet for the singles court.
Can a doubles serve land in the alley?
No. A doubles serve must land in the correct diagonal service box, which ends at the singles sideline. If it lands in the alley, it is a fault.
Does the line count as part of the alley?
Yes. The boundary line is in. In doubles, a ball touching the doubles sideline is good during a rally; in singles, the singles sideline is the relevant boundary.
Final Thoughts
The alleys are simple once you separate serves from rallies: they are out on every serve, in during doubles rallies, and out during singles play. Check which sidelines apply before a match, then use the extra doubles width with control. Aiming safely inside the line is often more effective than chasing the perfect shot right on it.
