The Aviemore brewer has secured a £665,000 finance package from Bank of Scotland plus £150,000 from Highlands and Islands Enterprise and £100,000 from the European Regional Development Fund to fund the work.
It is currently running the equipment a few days a week ahead of a formal launch early next year.
Then it hopes to take on bottling for other small breweries around Scotland and add to the four staff it has already taken on.
Managing director Samantha Faircliff said: "It gives us much more control over our own destiny. We are going to save costs as we no longer have to ship beer down on a lorry to England and it will also reduce our carbon footprint."
The brewery, which was founded in 2001, has been growing steadily in recent years and expects to report turnover of around £1.5m this year.
Ms Faircliff is predicting a rise in that figure next year and also hopes to add to the existing 18 staff.
She said: "When we take on bottling for other breweries then we will need to take on more people to cover the additional shifts which might be needed.
"When we looked at it, we knew we had to take a huge leap forward or scale back and we decided to go for it.
"I'm pleased to say we have had some very encouraging responses from other breweries thinking of entrusting their bottling to us and I am confident we will be handling the bottling requirements for a number of Scottish brewers when we become fully operational next year.
"Until now, exporting is something we have done by request but now we will have much more control on production so can target more markets."
Chief Secretary to the Treasury and local MP Danny Alexander was at the brewery yesterday to toast the launch of the Ginger Rodent beer brand.
The term was famously hurled at Mr Alexander by Labour's Harriet Harman in a party conference speech.
He said: "The investment here stands the company and the community in good stead and I look forward to it prospering."
Cairngorm Brewery makes beers including Stag, Wildcat and Nessie's Monster Mash.
Martin Johnson, from Highlands and Islands Enterprise, said: "Cairngorm Brewery is an excellent example of a small, innovative business being ambitious for its future. The improvement that a new bottling plant can provide will be a significant asset in expanding its customer base and increasing sales."