If You Are Ignoring Session-Based Broad Match, You Are Losing Money

by John A. Lee

Do I have your attention yet? Earlier this year, Google AdWords launched another addition to their PPC keyword-matching algorithm called Session-Based Broad Match. This is an extension of the typical broad match that we all know and love (*cough*). Frankly, Google made their announcement with little fanfare, and only a few advertisers have made mention since. Despite the lack of noise, I have personally made reviewing Search Query Reports for session-based queries a top priority. Why? For the most part I have found session-based queries to be consistently irrelevant, and I typically add them as negatives in my campaigns!  So, if you are ignoring session-based broad match, there’s a pretty good chance you are losing money in your AdWords campaigns.

Google’s goal with session-based broad match is to pair PPC ads with a larger cache of long tail keyword inventory. The core issue I have with this that the long tail keywords that Google deems “relevant” to your ad are frequently not relevant at all. The process goes as follows:

  • User types in a search query. Google evaluates this search query. Your ad may be triggered (or not).
  • User types in another query. Google evaluates this same user’s previous queries during the same session (thus the name!).
  • Google assesses these new queries and generates “similar terms” for that search.
  • Google cross-references these “similar terms” against the broad match keywords you’re bidding on in your AdWords account.
  • Google potentially shows your ad if the system detects a relationship between the new query and the previous query. Your ad may be triggered for “related keywords” that aren’t in your campaign.

What does that mean for you?

Well, it means the potential exists for irrelevant impressions and clicks. Take the following search queries for example. I’m using the keyword “black tea” in my campaign – and for some reason, Google has found a relationship between “black tea” and “mickey mouse teapot” and even “black sequin top”! Keep in mind, that all of the keywords in this ad group contain some variation of the root term “black tea” and yet my ads still appeared for these irrelevant search terms:

In this example, AdWords has displayed my ad for “black tea” on very irrelevant searches through session-based broad match. This has two negative implications. First, my ads are displayed to searchers who never wanted my product. They are less likely to click on my ad, and this will lower my click-through rate (CTR) and could potentially damage my Quality Score. Second, even when the search query and the ad are completely dissimilar, some of the people using the irrelevant search query will click on the ad – and these are the least unlikely site visitors to convert. This makes my campaign vulnerable to losing money through lower return-on-investment (ROI) and increased cost-per-acquisition (CPA).

How is Session-Based Broad Match different from Automatic Matching or expanded Broad Match?

This is best described with visuals. The first illustration explains how the process for Automatic Matching (and expanded Broad Match) matches a search query with your ads:

This second illustration shows how Session-Based Broad Match is a tangent from the normal flow between search query and ad delivery:

Unlike Automatic Matching, session-based broad match cannot be turned off. Accordingly, if you are bidding on broad match keywords, you must remain vigilant. Run search query reports on a regular basis and keep an eye out for those queries marked Broad (Session-Based). When you find queries that are completely off-base from your product or service, add them as negatives. Train Google to NOT match your ads with those search queries – otherwise, resign yourself to losing money!