Bristol City Council has pledged an extra £284,000 a year towards addiction services after it failed to attract any bids for a contract to run services.
Councillors heard on Tuesday that no firms had applied for the £1.2m-a-year deal to help the most complex cases.
Deputy mayor Asher Craig said companies felt £1.2m "was not sufficient".
Bristol has the highest proportion of people with complex substance abuse issues of any major city, according to Public Health England figures.
The contract was to deal with the city's most complex addiction cases, meaning people with multiple issues such as mental health problems or homelessness.
Bristol City Council spends £8m a year helping addicts through services such as ROADS (Recovery Orientated Alcohol and Drugs Service) which aims to reduce deaths and support people through treatment.
Tuesday's cabinet meeting heard that, instead of putting the contract out to tender again, the work would be shared among organisations already working in the field, which would receive the extra funding.
Ms Craig said: "The alternative approaches we looked at would have involved going back out to tender on the specialist service or starting a new commissioning service with one single contract, and that was just a route we didn't want to go down because it would have been too disruptive to the current service.
"Our Recovery Orientated Alcohol & Drugs Service (Roads) offers vital support some of the most vulnerable in our city. The Complex Needs section of this service works with some of those who are most at need of our support and are often living in very difficult circumstances.
"It is important that we get this service right so since we received no bids from providers to run this service last year we have been working hard with our partners across the city to develop an offer that will work for everyone.
"I am pleased that we have been able to announce that this section of the service has now been successfully re-commissioned which will mean that these complex cases will continue to receive the support they need."