Is a Straight Putter Illegal?

Affiliate Disclaimer

As an affiliate, we get paid from qualifying purchases made using the links in this post.

Regardless of whether you’re an amateur or professional golfer, chances are you’ll run across an illegal putter at one point or another. With a wide range of new ‘game-improvement putters out there, it’s difficult to determine which are legal and illegal during gameplay. Game-improvement putters like a straight putter help line up your putt and get you into a good stance. Depending on specific factors like the shape of your clubface, you may run into some trouble. 

There are many rules in place during tournament regulation play that you must abide by; otherwise, you’ll get an unfair advantage. In this article, we’ll answer the common question “is a straight putter illegal” and also tell you what makes an illegal putter. Let’s begin! 

Are Straight Putters Illegal? 

Yes, straight putters are illegal. Although it may sound counterintuitive, the shaft always must enter the club angle at an angle. Specifically, the shaft has to enter the clubhead at a minimum of 10 degrees and 25 degrees at most. Thus, croquet-style putters aren’t allowed. However, from the sole of the clubhead to five inches above, it must be straight. 

What Makes an Illegal Putter?

In order to understand what makes a putter illegal, you must know the rules. The United States Golf Association (USGA) has set various standards for all golf equipment, including putters. 

Loft angle

A putter can be characterized as a club with a loft angle of 10 degrees or less and is designed to be used on the greens. Although it’s recommended only to use the putter on the greens, nothing in the rules states that using a putter outside of the greens is prohibited. Thus, a putter must have a loft angle between -15 degrees and 10 degrees. Otherwise, it is illegal. For adjustable putters that can alter their loft angle, it mustn’t exceed these ranges; otherwise, it will be considered illegal. 


Putters must be 18 inches or longer, meaning anything that falls short of that would be deemed illegal. However, there isn’t a restriction on how long the length of the putter can be. The putter also cannot be integrated vertically into the clubhead. 

Clubface and Clubhead

The top of the grip measures the length down to the sole of the clubhead. Typically putter shafts are straight; however, if the shaft isn’t a straight line, a measurement will be made using a straight-line extension. 

Also, the putter cannot have a clubhead over 7 inches long; otherwise, it is illegal. Furthermore, the height of the club head cannot be greater than 2.5 inches, or it’s illegal. The width of the clubface must be equal to or greater than half of the clubhead’s width and two-thirds or more than the clubhead’s depth. 


A durometer is used to score or measure the hardness of the putter material. All putters must be measured at least 85 or above on the durometer. A putter that is too soft can give the putter a better feel and thus an unfair advantage. The putter shouldn’t have any visible signs of flex when pressure is exerted. 


A putter’s grip isn’t allowed to have significant bulges or curves. Furthermore, it must be relatively even and symmetrical in shape. For longer putters that may have two grips, both grips must be similar in shape, and the upper grip has to be five inches or longer. 


The top portion of the neck cannot be over five inches above the putter’s sole. The socket or neck can’t protrude outward in a horizontal direction over .84 inches from the center. 

Common Examples of Illegal Putters 

Some golfers will bring all kinds of putters to the course. Getting caught and being denied to play can be quite embarrassing. We’ll save you time by providing you with some common examples of illegal putters out there: 

  • Any putter with more than one striking face that isn’t identical to one another. Putters can only have multiple striking faces if they are identical in shape and size. 
  • Any putter that has a feature that extends over .84 inches away from the clubface. 
  • A putter that has two necks is illegal. According to the USGA rules, the putter can only have one neck that enters the club. 
  • Any putter with a curvy or non-straight neck. A putter’s shaft and neck must be straight. Specifically, the club must be straight from the sole of the putter head to five inches above it. 
  • A putter with a laser dot on it is illegal. Any putter with an electronic feature on it is prohibited. 
  • A putter without a striking face is illegal. 
  • A putter cannot have holes in them. That’s because the rules state that the putter must have a plain appearance. 

Can a Putter Be Too Straight?

Yes, as mentioned earlier, a putter that is entirely straight from the shaft to the clubhead isn’t allowed. However, some putters are straight and are capable of standing up vertically. Putters that can stand up on their own help players in lining up their putts. Despite some controversy, standalone putters are legal. According to the USGA, self-standing putters that aid in taking a stance or help align to the hole are allowed. 

What Types of Grips and Strokes are Prohibited? 

While putting, it’s also illegal to perform the anchoring grip. This means you cannot brace the end of the grip against your body during the stroke. You also are prohibited from bracing the forearm against your body or the top hand on the grip since these movements give you an anchor point. 

Is a Straight Putter Illegal – Conclusion  

Most putters are safe to use in tournament play. However, you may want to read up on the USGA rules or ask the manufacturer to double-check. The most common types of putters that may be banned are ‘game-improvement ones that change the design or include markers which can give you an unfair advantage over other competitors. We’ve hope you’ve gained a lot of insight as to what makes a putter illegal and how to stay clear from getting banned.