Gear4music's sales rose by 73% to £21.6m in the six months to the end of August with the active customer numbers increasing by 45% to 271,000.
UK sales rose by 44% to £13.8m while European sales increased by 169% to £7.8m.
Chief executive Andrew Wass said: "We are very pleased to have sustained the strong sales momentum announced on 29 July and achieved 73% like-for-like revenue growth during the half year, and overall profitability in the period will be ahead of management expectations as we head into the key second half trading period.
"This impressive growth reflects our focus on continual investment in and improvement of our product range, websites, systems and overall customer proposition, and the commitment of our hard working team. "Reassured by this sales growth, we are continuing to invest in the business, including establishing our first European distribution centre that will be located in Sweden, which we expect to be operational from November this year.
"This centre will improve our delivery times to customers throughout much of Scandinavia, whilst at the same time reducing delivery costs in those territories. We are also working towards opening a second European hub before the end of this calendar year.
"These first two distribution hubs will not only transform our European customer proposition, but also increase the overall capacity of our business to deliver over £100m revenues. This additional distribution capability will also be augmented with localisation of some purchasing and merchandising functions, ensuring the business is well placed for any Brexit eventuality."
At 9:29am: (LON:G4M) Gear4music Holdings Plc share price was +15p at 181.5p