Band manager Scott Muir said he would not ''confirm nor deny'' whether the band was booked to play at the festival in England in June.
Festival organisers did not announce artists set to perform before tickets went on sale, because the 135,000 tickets were always snapped up quickly regardless, he said.
''Glastonbury sell the festival - they don't sell the artists - and it sells out within its first 40 seconds [of tickets going on sale] and it does every time.''
If the band had been invited, it would have been sworn to secrecy until festival organisers announced the line-up, he said.
Mr Muir said if the band had been asked to play at Glastonbury, they would have accepted the invitation.
''I can't tell you any more than that.''
Singer Martin Phillipps said the Chills had never played Glastonbury.
Although he would not confirm if the Chills had been invited, the band would ''definitely'' be performing internationally this year, he said.
Glastonbury Festival starts on June 25 and finishes on June 29.
Festival-goers each paid $405 to attend last year's event, which was headlined by the Rolling Stones and the Arctic Monkeys.
Six60 bassist Chris Mac said when his band was invited to perform at the festival last year, it had about three months' notice and was sworn to secrecy until a week before its performance.
''You don't want to announce until the festival announces.''
New Zealand Music Commission international manager Gary Fortune said Glastonbury organisers wanted performers to keep quiet so they could control the announcements to the media.
''If someone at Glastonbury gets invited to play, they'll be told so they can accept the invitation and get themselves sorted out, but will be told to stay shtum until Glastonbury goes out and says here is the next wave of bands playing.''
A Glastonbury invitation was a great chance to be exposed to a large international audience, he said.
