How I could shoot under my handicap – and still see it go up

Something very curious can happen to me. I’m playing in a competition on Wednesday evening, and there’s a chance I shoot under my Course Handicap and still see my World Handicap System index increase.

Yes, you read that right. I could play a net-under-par round and my handicap may go up.

This isn’t a lottery win scenario. It’s not far-fetched. It simply requires a good round and some understanding of how WHS works.

So what’s going on? Is it a flaw in the system? Or just a bit of design most don’t really notice until it happens to us?

If you’re not a numbers person, bear with me. Even I’m hoping my maths are right. But, at heart, this is a story about one great round… and nearly two years of inconsistency.

WHS index increase after good round: When playing well doesn’t help your handicap

I’ve got the golf bug again. I’ve fallen hard. But my time on the course has been patchy, largely due to family life (hello, small child).

It means my WHS record of 20 scores goes back to October 8, 2023. It’s a date I remember because it’s by far the best round in that list – the last time I really played well.

That round, a gross 80, produced a Scoring Differential of 9.6.

It’s been tough going since. My handicap index has risen from 11.3 to 13.6, and the seven other rounds currently “counting” towards that handicap? Well, they’re not so good:

15.2, 14.5. 13.7, 12.8, 14.5, 14.5, 13.6

What is a Scoring Differential?

Good question. The USGA says it’s a number that “measures the performance of a round in relation to the relative difficulty of the course that was played, measured by Course Rating and Slope Rating”.

Your best eight differentials out of the last 20 are averaged and the number that spits out is your Handicap Index.

Here’s the twist.

That 9.6? It’s been doing a lot of heavy lifting and it’s about to fall out of my last 20. Once it’s gone, forget about it. What comes next is what’s interesting.

Let’s look at a hypothetical. Say I shoot 86 on my Par-73 course. With a Course Rating of 73.2 and a Slope of 132, my Course Handicap will be 16. I’ve just shot three under.

Get the shears out, you say. I hear you. But a differential calculator tells me that round will produce a scoring differential of 11.0.

It’s good, easily the superior number in my new average of eight best, but it’s not as great as the 9.6 it’s replacing.

With everything else remaining the same, the 11.0 goes in, the 9.6 comes out and the average of my best eight differentials increases slightly.

The result is my Handicap Index rises, even though I’ve just played better than my Course Handicap.

I reckon it would go from 13.6 to 13.7. Add the numbers up in the table below, divide them by eight, and you can see for yourself.

Even a Great Round Can Raise Your Handicap

No Caps, No Miracle

I wouldn’t be affected by the Soft Cap, which slows down the rate my index can go up once it’s increased three strokes in a 12-month window.

Nor do I hit the Hard Cap, which stops my index from rising more than five strokes from my lowest point in the last year.

So I can still go up, even if I shoot a round under my Course Handicap.

If you’re used to the old CONGU system, this kind of eventuality might feel wrong. Going under-par almost always triggered an immediate cut back then. WHS is different.

Is it a flaw? It might feel like one, but it’s the system doing what it’s designed to do. It’s meant to reflect your averaging scoring, not the best single round.

But if you play well and you’re handicap still goes up?

Well… that sure feels strange.  

Update: You might be wondering what I did shoot after all that. In the end, it was 84. That resulted in a scoring differential of 9.2 and a WHS Index cut of 0.1.

Now have your say

WHS increase after good round: What do you think? Have you ever posted a round under your Course Handicap but still seen your WHS Index increase? Should it be permitted under WHS rules, or should a round that goes low always mean a cut? Let me know by emailing me at s.carroll@nationalclubgolfer.com or by dropping us a line on X.

• NOW READ: How many scores count towards my handicap? What happens if I don’t have them?

• NOW READ: Why doesn’t this lower score count for my handicap?