Perrior took leave from the business, which she set up with Jo Tanner in 2006, in June in order to help Theresa May's bid to become Prime Minister
She was rewarded with a full-time role once May entered Downing Street, and sold her stake in the agency, whose clients include Starbucks, News UK and Diageo.
Melanie Onn, the Labour MP for Greater Grimsby, has tabled a total of 16 questions this week and last week on whether various departments have awarded any contracts to iNHouse in the last five years, or whether they are in communication with the agency over any tender processes.
A spokesperson for the agency told PRWeek: "We have no Government contracts. The only service we have ever provided to the Department for Education in the past is when they have used our innovative Connex [telephony service] technology."
The Ministry of Defence and Department for Business, Energy and Industrial Strategy have responded that they have not awarded them any contracts in the last five years, with the former also saying it would not be able to answer the question about whether they had liaised over tender processes, as this information "is not held centrally and could be provided only at disproportionate cost".
Other questions are still to be answered.
A senior Labour source told PRWeek: "Given Katie Perrior's role at Number 10 it's important that any commercial relationships her previous company may have with Government departments is made public in the interests of transparency."