The company's bottom line was boosted by strong gains in mobile search and YouTube advertising, while it kept a tight lid on expenses.
"Our Q3 results show the strength of Google's business, particularly in mobile search. With six products now having more than 1 billion users globally, we're excited about the opportunities ahead of Google, and across Alphabet,” said Ruth Porat, CFO of Alphabet and Google.
Third-quarter revenue rose to $18.68 billion from $16.52 billion a year earlier.
Net income rose to $3.98 billion, or $5.73 per Class A and B share, from $2.74 billion, or $3.98 per share in the same quarter last year.
Excluding one-time items, the company earned $7.35 per share.
Expenses rose 9.1 percent to $13.97 billion but were 74.7 percent of total revenue, compared to 77.4 percent in the same quarter last year.
The company said advertising revenue increased 13 percent to $16.78 billion in the three months ended Sept. 30, while the number of total paid clicks rose 23 percent, compared to an 18 percent increase in the previous quarter.
Cost-per-click, or the average price of online ads fell 11 percent in the quarter.
The results are the first since Google officially changed its name on Oct. 2 as part of an overhaul of its operating structure, with Alphabet acting as a holding company. Under the restructuring, search, advertising, maps, YouTube and Android will remain part of Google.