U.S. bank Citi and polling firm YouGov said their gauge of expectations for inflation in five to 10 years' time held at 4.2% in May, unchanged from April.
Public inflation expectations for the coming 12 months edged up to 6.1%, matching March's record high, from 6.0% in April.
Citi economist Benjamin Nabarro said the figures were likely to mean the BoE remains concerned about medium-term inflation expectations.
"However, we see little in today's data that should provide a further impetus for an out-sized 50bps move," he said, referring to the possibility of a half percentage-point interest rate increase.
(Writing by William Schomberg, editing by Andy Bruce)