Nicholson has worked on launches including Best and Prima Baby, before becoming Good Housekeeping's editor-in-chief in 1999.
She said that despite the magazine "flying right now", she looked forward to taking on the new role once an editor for Good Housekeeping has been found.
Nicholson said: "The opportunity to be involved in launches and relaunches across a wider portfolio is one that no editor worth her salt would turn down."
Duncan Edwards, NatMags managing director, said the company's recent growth had made him conscious of the need for a senior editorial leader.
Edwards said: "Lindsay was an obvious choice as she has been successful in launching and editing large-scale magazines."
The company's growth also led Edwards to bring in Jessica Burley, formerly the chief operating officer of the company's weekly magazines joint venture with Australian publisher ACP, as managing director in December.
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