The Blues qualified for the last 16 as winners of Group E courtesy of Demba Ba's 10th-minute strike at Stamford Bridge.
Terry suggested that the 2011 winners fancy their chances of success in the knockout stages of the competition under Jose Mourinho.
"We are still improving and can get better for sure," the 33-year-old told Sky Sports News.
"It was important for us to top the group tonight, some tough teams have topped the groups.
"We'll go about our business, we are through now, to top it is a bonus. We are quietly confident, we know we have to get better and improve."
The West Londoners will play either Bayer Leverkusen, Galatasaray, Olympiacos, Zenit St Petersburg or AC Milan in the next round.