unofficial
adjective
uk/ˌʌnəˈfɪʃəl/ usnot officially approved by a person in authority, the government, etc.:
unofficial estimates/figures/targets Profits were below unofficial estimates.
unofficial data/reports/results Based on early and unofficial data, the Dow Jones industrial average fell 10.12 points.
not part of an official plan or someone's official business:
an unofficial policy/visit The company has an unofficial policy of allowing a number of houses to fall into disrepair before seeking private contractors to do the work.
Compare
official adjective
unofficially
adverb
He said he had been given the information unofficially.