Sandwell Council will launch a consultation on proposals which will cover a range of options from closure to combining services with community centres and libraries being run by more volunteers.
The five libraries being reviewed are Hill Top in West Bromwich, Oakham in Tividale and Langley, and Brandhall and Rounds Green, all in Oldbury, which bosses say are the 'quietest' in the borough.
But they say shutting them would be a 'last resort' and they would look at ways to keep them open although they admit jobs are at risk under the review. The options include converting them into smaller 'express' libraries and moving them to different sites with staff provided by other organisations.
They will also consider moving them to alternative premises, keeping them open on the same sites but either run by more volunteers or with sharing the buildings with other services. The final option will be to keep them the same. A decision on the future of the libraries will be made before the end of the year.
Deputy leader Councillor Mahboob Hussain said: "We have protected frontline services as much as we can through years of cuts to the council's budget and will continue to do so.
"Libraries provide a great service and are popular with local people. In recent years we have opened new libraries in Blackheath and Oldbury and invested in West Bromwich Central Library.
"However, we have to be realistic – we need to save a further £700,000 from the library budget over the next two years and must look at every option. The major costs of the service are staff and buildings, but the closure of any library is the absolute last result and I am hopeful we can find another way.
"There are three main suggestions, including working with volunteers and community partners, moving libraries into shared premises or bringing other services into libraries to reduce running costs and provide multi-use centres for local people.
"Options are simply that, they are not set in stone.
"We will ask people for their views and take a final decision by the end of the year."
The library services has already had to face cuts of £1.5m between 2011/12 and 2014/15.