Yahoo search users in the UK, Ireland and France will start to see ads from Microsoft’s adCenter next week, as the two companies wrap up the transition that began in 2009 with the MSFT-Yahoo search alliance.

As part of the transition, search advertisers that are still on Yahoo’s platform in those countries will need to migrate to adCenter because Yahoo Search Marketing accounts will shift to read-only status. But, in a blog post today about the pending change, Microsoft suggests monitoring both accounts during the transition:

As Yahoo! ad serving moves to adCenter, and your clicks and impressions in that account begin to increase, you’ll see a corresponding decrease in clicks and impressions in your Yahoo! Search Marketing account. It is thus important to continue managing your campaigns across both platforms throughout this transition phase, in order to avoid missing out on any potential clicks.

The transition is expected to begin “as early as” January April 18th and be complete by the end of the month. [Ed. note: Apologies for the typo there on the month!]

Microsoft says the transition is coming later this year to Germany, Austria and Switzerland.

Related Topics: Channel: SEM | Microsoft & Yahoo Search Deal | Microsoft: Bing Ads | Microsoft: Outside US | Top News | Yahoo: Outside US | Yahoo: Search Ads

About The Author: Matt McGee is Editor-In-Chief of Search Engine Land. His news career includes time spent in TV, radio, and print journalism. His web career continues to include a small number of SEO and social media consulting clients, as well as regular speaking engagements at marketing events around the U.S. He blogs at Small Business Search Marketing and can be found on Twitter at @MattMcGee and/or on Google Plus. You can read Matt's disclosures on his personal blog. See more articles by Matt McGee

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