Two plumbing firms advertising themselves as local in areas such as Rickmansworth, while actually based in Southampton, were fined by Watford Magistrates's Court on 1 April.
1st Active Drainage Ltd, and sub-contractor John Noel Moris each pleaded guilty to six charges under the Consumer Protection from Unfair Trading Regulations Act 2008.
Following complaints from customers in Buntingford, Rickmansworth, and Ware in Hertfordshire, Trading Standards found that calls to a series of local numbers were transferred to 1st Active Drainage.
The company, with offices in Southampton, then sub-contracted the work to Moris, 54, who was based near Leamington Spa in Warwickshire.
The three customers had contacted the firm when their drains became blocked and said they would not have agreed to someone coming that far.