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Everything you need to know before hiring a CRO agency

Article originally published in November 2022 by Stuart Brameld. Most recent update in April 2024.

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Why you (probably) need a cro agency?

Pageviews, impressions, clicks and opens are worth nothing if you are unable to convince prospects and buyers to take some action. Regardless of how you get people to your site – whether via organic search, email marketing, or paid acquisition – it is getting increasingly more expensive (and competitive) to get traffic online hence the importance of getting the most value out of every visitor.

We often see companies spending huge amounts of time and money on paid advertising – on keyword research, going back and forth with agencies on creative and constant tweaking of ad targeting – all whilst pointing to an unoptimised and poorly converting landing page.

Conversion rate optimisation (CRO) is the scientific process by which you get more from your existing marketing spend and campaign activity. With conversion rate optimisation and a CRO agency you can:

  1. Increase the percentage of visitors to your website, landing page or online marketing campaign that take a desired action
  2. Identify the user struggles and objections that result in people dropping out of your marketing and sales funnels
  3. Increase the percentage of visitors that convert to leads and sales

A small increase in conversion rates can result in big increases in revenue, particularly for B2B companies that have larger deal sizes. For a website that receives 10,000 visitors a month and converts 1% of those visitors to MQLs, that’s 100 MQLs per month. A relatively modest increase in conversion rate from 1% to 3% would result in an additional 200 leads. For a mid-market business with an average contract value of £20,000, with a 5% MQL to SQL conversion rate, that modest conversion rate improvement equates to an additional £200,000 of sales pipeline a month, or £2.4M a year.

It’s much easier to double your business by doubling your conversion rate than by doubling your traffic.

Jeff Eisenberg

What does a CRO agency do?

Conversion rate optimisation is similar to the growth marketing process, rooted in an iterative, agile approach to testing, measuring and learning.

We’ll cover the three main areas of conversion rate optimisation below – performing research, generating hypotheses and testing.

1. Perform CRO research

Stripped down to its basics, conversion rate optimisation (CRO) is about understanding why your visitors aren’t converting, and deciding what to do about it.

However, as with growth marketing process in general, the mistake most businesses make is skipping the research and jumping straight into generating new ideas and experiences. We take the Abraham Lincoln approach to CRO and experimentation, where research and preparation are the keys to success.

“If I only had an hour to chop down a tree, I would spend the first 45 minutes sharpening my axe.”

Abraham Lincoln

The first step in any conversion rate optimisation process is to perform in-depth research in order to remove guesswork and bias from decision making. Conversion rate optimisation, and experimentation, are both visitor-centric practises, rooted in data and an understanding of customers.

This research phase may include a range of different analysis in order to understand user struggles and objectives that drive funnel drop-offs, this may include:

  • Website traffic analysis
  • User testing
  • User polls and interviews
  • Event map analysis
  • Heat maps & scroll maps
  • Video session recordings
  • Customer interviews
  • Customer surveys

It is often help to also include competitor research as part of this research phase.

2. Generate CRO test hypotheses

Similar to the growth marketing process, after performing thorough research in order to identify customer struggles and objections, a cro agency will create a number of hypotheses design to address the issues.

Typically a number of test hypotheses will be created, and then prioritised with the aim of initially finding the quick wins, where results will have the biggest impact for the business.

During this hypothesis and idea creation phase, an agency may ask questions such as:

  1. Where are people dropping off in the buyers journey and why?
  2. Which channels are delivering the most high-converting traffic?
  3. Which ads and campaigns are resulting in the most sales?

3. Create and run CRO tests

Once high priority CRO tests have been identified these will be turned into alternative variations and setup for testing, typically using 3rd party testing software such as VWO.

CRO is the most important marketing activity because it makes every visitor exponentially more valuable.

Rand Fishkin, Moz, SparkToro

Depending on the complexity of your website or application and the proposed test this may include work such as:

  1. Developing a solution concept or concepts
  2. Designing the alternative variation(s)
  3. User testing the alternative variation(s)
  4. Coding of the alternative variation into the experiment
  5. Setting up relevant goal and conversion tracking
  6. Performing post-test statistical analysis

For simple website CRO testing using existing test infrastructure, tests may be able to created in minutes rather than hours. For more complex engagements, CRO agencies may provide adjacent complementary services covering the entire customer journey, such as data and analytics audits, email marketing, website personalisation, pricing experimentation and referral programmes.

What are some conversion rate optimisation (CRO) examples?

Here are some public examples of conversion rate optimisation successes.

Conversion.com worked with Voices.com, a leading marketplace for voice-over talent, to increase website conversion rates by 400% over the course of 11 conversion rate optimisation experiments. Experiments included adding social proof in the form of happy companies, segmenting website visitors, creating demonstration videos and email marketing.

Conversion rate experts worked with Moz.com, the provider of SEO and inbound marketing software. The first split test CRE ran for Moz generated a 52% improvement in sales, and within the first 4 months of work annual revenues increased by $1 million. Experiments included a more long-form, content rich homepage, added a chart to show all features, added existing client logos and testimonials and testing new calls-to-action.

What kinds of software does a CRO agency use?

We’ve collated a number of conversion rate optimisation tools from our internal database below. Please contact us for an up to date copy, or if you would like a csv/xls export of this list.

How do CRO agencies charge for services?

Typically a CRO agency will charge based on one of the models below, or all 3:

  1. A one-off CRO audit and review, where funnel inefficiencies are identified along with barriers to conversion and compiled into a one-off report. This is generally the lowest cost option, though also likely to produce the least conversion uplift.
  2. Performance-based CRO, where you only pay for growth of key metrics. The advantage is that it’s easy to calculate return-on-investment, the disadvantage is that this is definitely not the norm and performance-based pricing is generally the most expensive.
  3. A CRO retainer with no guarantee, where you pay for an amount of ongoing optimisation. This is by far the most common method of charging and provides for continual, ongoing optimisation work.
  4. A CRO retainer with guarantee, where you pay for an amount of ongoing optimisation but where this is a guaranteed uplift in your chosen metric (usually between 1% and 5%).

Who are some of the best conversion rate optimisation agencies?

In no particularly order here are, in our opinion, the best b2b conversion rate optimisation agencies you should consider working with.

  1. https://purplefire.io/conversion-rate-optimization/
  2. https://conversion.com/
  3. https://conversionadvocates.com/
  4. https://conversionfanatics.com/
  5. https://conversion-rate-experts.com/
  6. https://northpeak.io/
  7. https://sitetuners.com/
  8. https://www.ground.co.uk/
  9. https://vwo.com/services
  10. https://conversionfanatics.com/
  11. https://www.widerfunnel.com/
  12. https://www.invespcro.com/
  13. https://crometrics.com/
  14. https://experimentzone.com/
  15. https://www.journeyfurther.com/

Which one is the best CRO agency for me?

We can’t tell you that, but, based on our experience we have put together the questions below to consider when looking to hire a CRO agency or consultant:

  1. Are they a pure-play CRO agency, or offering CRO as part of more generalist agency services, such as web design, development and creative?
  2. Is there a process that has been defined through working with a large range of clients that they can confidently talk you through and explain?
  3. Request a short call or strategy session, maximum 30 minutes, in order that they can provide some initial thoughts. Companies such as Conversion Rate Experts that are confident in their ability to deliver should offer a free strategy session. An experience agency will be able to ask good questions and make concrete suggestions solely based on your public website.
  4. Do they have experience with your kind of business, and in your sector? A number of CRO agencies focus solely on e-commerce and B2C, working specifically with technology platforms such as Shopify and WooCommerce.
  5. Review case studies and testimonials, ask for case studies and references for your industry.
  6. Which acquisition channels and tools do they specialise in, and how do these complement existing in-house tools and capabilities?

CRO & CRO agency resources

Here are a few of the best conversion rate optimisation resources for further reading:

  1. Conversion Rate Experts articles library https://conversion-rate-experts.com/articles/
  2. The Conversion Rate Experts methodology https://conversion-rate-experts.com/our-methodology/
  3. Experimentation Nation CRO qualification exam resources https://experimentnation.com/resources-to-help-you-prepare-for-the-experiment-nation-cro-qualification-exam/