Spelling rule- ‘The Floss Rule’

Spelling rule- ‘The Floss Rule’


ff, ll, ss, zz rule anchor chart

Floss Rule anchor chart


Click on the above image to download the poster

Why does ‘bell’ have a double ‘l?’
Why does ‘buff’ have a double ‘f?’
Why does ‘miss’ have a double ‘s?’
Why does ‘buzz’ have a double ‘z?’

Have you ever wondered why some words end in a double consonant?
The reason for this is the spelling rule which we call the floss rule.

What is Floss rule?

If a word has only one vowel and ends with f, l, s or z; double the consonant. So, under this rule s  is spelled ss, l is spelled ll, f is spelled ff, and z is spelled zz.

The spelling rule is one of the first rules that I teach beginning spellers.

The -ll and -ss ending is the most common. The -ff ending is less common and -zz is not a very common ending.

You must be wondering why it is called the FLoSS rule. Floss has f, l and s so under the floss rule /f/, /l/ and /s/(/z/) are doubled.  I know the word ‘floss’ does not include ‘z’ but it’s okay since there are very few words that end in /z/.

There are a few exceptions to the rule. For example: if, of, is, gal, gas, bus, yes etc. In all these words f, l and s come after a short vowel but they are not doubled. Quiz is a word that does not end with a /zz/.

Next, I am going to share a simple word list for this rule with you. Please print it out and have our little readers read it. The child can choose to highlight the double consonants with a light color.


floss rule word list for kindergarten and grade 1

floss rule word list


The above list is a phonics word list for ff ll ss zz words.

You can also find Floss rule worksheets on my website to practice the rule.

I hope you find this spelling rule lesson useful.