Brilliant previously held the TV account and Brand Connection managed the press activity.
Chris Gooding, group marketing director of HomeForm, said: "We moved our £10m TV business to Brilliant over two years ago and because of its performance to date, we felt it made perfect sense to integrate TV and press planning and buying within a single media agency.
"Our annual investment in media advertising is substantial and we feel that they are ideally placed to get the most out of that investment."
HomeForm has annual sales of over £200m and spent over £19m on advertising in the past 12 months, with Moben the biggest spender at £7.3m.
Steve Lane, chief executive of Brilliant, said: "Organic growth from an existing client is the ultimate endorsement of our input and service, and we are delighted to be extending our role and relationship with the UK's leading home improvement brands."
Brilliant Media is a privately owned UK media agency with offices in Leeds and Manchester and billings of £130m.
The agency recently won the £8m Subaru account and the £12m regional assignment for supermarket giant Asda in the summer.
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