118 civilian jobs are due to go by the end of the summer at Dyfed Powys Police.
The force, which employs more than 800 staff, says the restructuring comes as the UK Government aims to reduce its budget.
The commissioner's office says no police officers will be made redundant or PCSOs. The Unison union is being consulted.
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Blackwood mother Trudy Jones was on holiday when she was gunned down in the Tunisian beach massacre that claimed the lives of 30 Britons.
The pair, including a man in his 50s, were struck around midday on the Pen y Fan mountain range in Powys, mid-Wales.
The former Wales international and convicted rapist Ched Evans is expecting a baby with his fiancee, Natasha Massey.