Are All 800 Numbers Treated Equal?

Whether it’s the power of subconscious perception or reasoned logic, subtle clues on a web page can strongly impact our behavior on that site. Take for example the display of toll-free phone numbers. Most sites invite calls from visitors by prominently displaying their phone number on their web pages. Many times, these numbers are of the toll-free variety, with prefixes of “800”, “888”, “877” or “866”.

Although the “800” prefix has been around for over 40 years, its next oldest sibling, “888” is only 13 years old. The “877” prefix came about 11 years ago, while the youngest “866” has only been in use for 9 years.

Does the longer legacy of the “800” prefix result in higher conversions when tested against the newer toll-free prefixes?

We utilized our call tracking software to create a test that would determine if the use of various toll-free prefixes produced different conversion rates. We wanted to measure the impact the different prefixes had on both call-in conversions and online conversions.

Our sample included 18,100 visits to one lead generation site. All visits were from paid search ads in Google and resulted in 2,614 combined call-in and online conversions. The visits were split evenly among 4 distinct landing pages, each page displaying a different toll free number. Other than the different phone numbers, the landing pages were identical. All visits were recorded during the 1st quarter of 2009.

Chart A shows conversion rates for call-in leads by prefix. Interestingly, our highest conversion rate corresponds to the oldest prefix (800) and the lowest conversion rate corresponds to the youngest prefix (866). Thus, the age of the prefix appears to directly impact the call-in conversion rate. The longer the prefix has existed, the higher its conversion rate. The magnitude of the difference between the best performing “800” prefix and worst performing “866” prefixes is 1.64 percentage points. This means that the “800” prefix had a 59.8% higher call-in conversion rate than the identical page with an “866” phone number.


Can different toll-free prefixes impact the online (form fills) conversion rate? As expected, while the results on call-in conversions were significant, the impact on online conversions (form fills) was somewhat less than conclusive as seen in Chart B.


The toll-free prefix that accompanied the page yielding the highest online conversion rate was “888”, followed closely by “866”. The “800” and “877” prefixes converted almost identically for online conversions. The spread between the highest and lowest conversion rates was .76 percentage points, less than half that of the difference in call-in conversion rates. Notice how these conversion rate results were almost opposite that of call-in conversions.

Chart C shows the results of our test on with the combined conversion rates. Notice now that the “888” and “800” prefixes convert at almost the same rate followed by the “877” and then the “866” prefixes.


If we place the same value to a call-in lead as an online lead, we can see in Chart D the projected revenues from the four prefixes. For the purposes of this exercise, we assumed that the value of a lead is $100.


Based on our observed combined conversion rates, the page with the “888” prefix would generate the most revenue.

In some instances, though, companies might place a higher value from a call-in lead. Sometimes call-in leads come from more highly motivated prospects, or prospects with a greater sense of urgency. If we were to value a call-in lead at twice (average order value of $200) that of an online lead (average order value of $100), the results become more striking.

The page with the “888” prefix clearly brings in the most revenue indicative of the strong call-in conversion rate for that prefix. In fact, the “888” prefix would generate 19.5% more revenue than the page with the”866″ prefix.

Based on our study, the greater the difference between the average order value of the prefixes, the greater the impact expected on revenue generated.

Here are two important take-aways from our study:

  1. As part of your landing page testing and optimization, you should perform a similar test to see if there are opportunities to increase your conversion rates. Call tracking software makes this an easy and inexpensive test.
  2. Understand the values of both your call-in and online conversions and factor that into your results. For ecommerce companies, a call-in sale gives the opportunity for an upsell, potentially increasing the average order value of call-in leads. Lead generation companies may also benefit more from call-in leads by being able to capture the prospect when the prospect is most interested and motivated to discuss their needs.