Hoste will take on the role from November, with independent retailer Ramesh Shingadia continuing in the role of vice chair.
The ACS represents over 33,500 local shops, supporting members through lobbying, advice and networking opportunities.
Hoste joined Spar during September 2019, coming to the business having worked for Walmart in the UK, Canada and Chile in commercial, customer and general management roles.
ACS chief executive James Lowman said: “Under Debbie’s inspirational leadership ACS significantly enhanced our support for both retailers and suppliers, and we look to the future in a stronger position than ever.”
Hoste said: “Local convenience stores have shown how important they are to the communities that we live in.
“They enhance and enable them to thrive. I want to ensure that we capture the momentum that now exists for local stores, and through using the latest innovations and listening to customers we can provide a relevant and progressive offer for our membership.”
Shingadia added: “I am absolutely delighted to be elected to serve on the ACS Board as the Vice Chair. It is a great honour and privilege.”