Worldwide revenue was $20.8 billion.
Inc on Thursday forecast first-quarter sales below Wall Street estimates, as it faces regulatory hurdles in India and a slowdown in e-commerce sales in Europe.
Shares of the company fell 5 percent to $1,635 after the bell.
The company's profits for the quarter were also up, reaching three billion dollars (£2.2 billion), compared to 1.9 billion dollars (£1.5 billion) this time previous year.
Stock. Jumped 3% in after-hours trading on the earnings report.
Amazon's profits were up dramatically year-over-year as well. The company has more than 100 million Prime members globally.
First published January 31, 1: 26 p.m. PT. Update, 2:14 p.m. PT: More details added throughout. Net income was US$6.04 per share, compared with an average estimate of US$5.56.
Amazon's self-proclaimed record-breaking holiday season also came with record costs for shipping billions of items to customers' doors.
Nicholas Hyett, analyst at Hargreaves Lansdown, said the online retailer was "tightening its grip" on its customers with add-on services such as Amazon Prime which offer free delivery and other benefits.
Additionally, the company's net income increased to $3.0 billion United States dollars (roughly $3.94 billion CAD) in Q4 2018, compared to $1.9 billion USD (roughly $2.49 billion CAD) in Q4 2017.
Chief executive Jeff Bezos highlighted the role of Amazon's digital assistant Alexa as the company moves into infusing artificial intelligence into its smart speakers and other devices in a race for dominance in the "internet of things" market. Its market cap, more than $840bn as of Thursday afternoon, is the largest of any publicly traded company in the world.
Still, a tight labor market, rising shipping costs and money-losing investments overseas remain threats.
Amazon is expected to roll out the attribution tool more widely this year, and advertisers say the early results were already promising, showing that Amazon ads are driving sales.
Annual net income increased to $10.1 billion United States dollars (roughly $13.26 billion CAD) in 2018, compared to $3.0 billion USD (roughly $3.94 billion CAD) in 2017.
"History shows that Amazon has had limited success in exceeding Street expectations for revenue in 4Q, likely due to the lack of visibility at the time guidance is given, and difficulties in forecasting a high amount of sales volume in such a small window", Suntrust analysts wrote in a note to clients.
Amazon has historically delivered relatively little profit as it fulfills Bezos's strategy of investing to stay ahead. In-store pickups of online grocery orders don't count as physical store sales, further clouding the ability to track the performance of Amazon's grocery push.