top of page
  • amandamcgerald

Understanding Hair Color: What exactly is a Single Process Color?

Updated: Feb 24


Smiling woman holding a clock waiting for her hair to process

As a master colorist, I have had many clients come in and ask for a "single process color". While this term is widely used in the hair industry, it can mean different things depending on the salon and stylist. In this blog post, I will explain what single process color is, and its different variations.



What is Single Process Color?

Simply put, single process color is a hair coloring technique that involves applying a single color that pulls through all the hair in one step. This is typically used to cover gray hair or change the overall color of the hair. The color is applied to the roots and then pulled through the mid-lengths and ends of the hair, creating a uniform color throughout.


Single process color, often referred to as "all-over color" or "base color," is a hair coloring technique that covers the entire head of hair in a single step. It is a straightforward and efficient process, making it a popular choice for individuals seeking a simple and quick hair color change. Unlike some other coloring techniques, single process color does not use foils. If you're curious about the foiling process and want to delve deeper into the details, you can explore a comprehensive guide in one of my articles here.  


Prepping Hair for Color

A developer is usually chosen to activate the color formula for application ranging from 10 to 40 volume, 10 being the lightest, and 40 being the strongest.  


If trying to go lighter from your natural hair tones, a gentle hair bleach might be used, but there are other lighteners available as a bleach alternative, such a REDKEN’s Blonde Icing.


Our stylists, as any professional colorist would do, make sure to consider your hair type, and at home hair habits when it comes to choosing the right combination of developer and color for your hair.



Variations of Single Process Color

While single process color is a simple technique, there are variations that can be used to achieve different results. Here are some of the most common variations:


hair stylist applying color to client's hair by hand

Demi-Permanent Color

Demi-permanent color is a type of single process color that uses a low-volume developer and deposits color onto the hair without lifting the natural pigment. This type of color typically lasts up to 24 washes, making it a good option for those who want to try out a new color without committing to it long-term.


Demi-permanent color is also great for adding shine and enhancing the natural color of the hair. It can be used to darken the hair by a few shades, but it cannot lighten the hair.


Permanent Color

Permanent color is another type of single process color that uses a higher-volume developer to lift the natural pigment and deposit new color onto the hair. This type of color typically lasts until the hair grows out or is cut.


Permanent color is great for covering gray hair and completely changing the hair color. It can be used to lighten the hair by several shades, but it may require multiple applications to achieve the desired result.


Note : A Single Process Color can be both Permanent and Demi-Perminant, depending on the client’s goals.


The Root Touch-Up

dark hair color regrowth

All about the re-growth!  Root touch-up is a variation of single process color that is used to cover up new hair growth at the roots. This technique is typically done between full color treatments to maintain a consistent hair color. It involves applying color only to the roots of the hair, where new growth occurs. This helps to blend the new growth with the rest of the hair and maintain a seamless color.


Root touch-up can be done with either demi-permanent or permanent color, depending on the desired result and the natural hair color of the client. It is a quick and easy way to maintain hair color and keep it looking fresh.


Glazing aka Toning

applying color toner to hair at shampoo bowl

Single Process Colors are typically accompanied with a Glaze.


Glazing, also referred to as a Toner, is another variation of a single process color that involves applying a clear or tinted gloss to the hair. This technique helps to add shine and enhance the natural color of the hair, without changing the overall color.


Glazing can be done on any hair type or color and is a great option for those looking for a subtle change or enhancement. It can be done with either demi-permanent or permanent color, depending on the desired result.


Toning is also a great way to blend in some of those natural changes in hair color.  For example, if you have dark hair and are growing some sliver highlights, applying a Toner or Glaze is a great way to downplay any drastic color difference. You can read here about gracefully embracing that hair evolution.




The Double Process Color

A double process color is a technique involving two big steps in achieving a dramatic change in hair color.


It is commonly used for achieving blonde or pastel shades, as these colors often require lifting the natural pigment from the hair before depositing the desired color. This technique allows for precise control over the color outcome, and is often utilized when needing to do a Color Correction, or for dramatic color changes in for achieving lighter shades, particularly for individuals with darker hair. 


First step is the overall Lightening of the hair, with the second step being an additional Single Process with Toning to achieve the desired shade.


Can You Do an SPC over Highlights

Absolutely!  This is a common technique once your color formula is set and creates amazing dimension. This technique is also common when doing a Color Correction service.



To Summarize...

Single process color is a popular and versatile hair coloring technique that can be used to achieve a variety of different looks. Demi-permanent, permanent, root touch-up, and toning are all variations of single process color that can be used to achieve different results. If deciding which type of single process color to choose, it's important to consult with a professional stylist who can help determine the best option based on your hair type, natural color, and desired result.  Don't forget, your desired look is our priority ;) 

202 views0 comments
bottom of page