An extra councillor could be elected to the Town Hall next year, giving the SIC 23 elected representatives.
Boundaries Scotland has submitted final proposals for councillor numbers and wards to Scottish Ministers.
The commission says it would be in the interests of “effective and convenient local government” for Shetland to be represented by 23 councillors in seven wards.
That could comprise one ward returning two members (Shetland West), while three wards would return three councillors (North Isles, Shetland North and Lerwick North and Bressay).
Four councillors could meanwhile represent Shetland Central, Lerwick South and Shetland South.
Council Convener Malcolm Bell said: “The council engaged with Boundaries Scotland’s consultation that took place in 2019 and I note the final proposals that are being put forward to Scottish ministers.
“Having a strong representative democracy is so important to Shetland’s future, and we will soon be starting our work to encourage candidates to stand for election.
“So, this report comes at an important time, with the local council elections now less than a year away.”