Financial services have seen the biggest loss in trust in privacy among consumers across 10 industries, a new survey from Deloitte says.

Of the 10 categories, insurers, banks and other financial services have seen the most significant drop in their score since the survey began in 2015, Deloitte says in its latest Privacy Index report.

However, financial services still score in positive territory showing more consumers trust than distrust financial services brands with their personal information.

The index says none of Australia’s top 100 consumer brands met best-practice guidelines for gaining consent to use customers’ personal information.

The results of the survey of 1000 Australian consumers finds retail is the best-performing sector when it comes to consumer consent, while health and fitness, finance, and telecommunications and media were the worst.

No sector scored above 30% when its consent practices were tested, demonstrating “industry-wide and regulatory immaturity”.

Some 83% of consumers were concerned internet cookies would track their activity online and use this information for marketing purposes or to sell information to third parties.

“Obtaining consent in the right way is critical for building consumer trust,” Deloitte National Privacy and Data Protection Partner David Batch said.

None of the top 100 consumer brands met consent best practices for cookie management and only 52% obtain consent for non-essential cookies through the bundled consent of accepting a privacy policy.

It is the responsibility of every organisation in Australia that accesses and processes personal information to do its bit in increasing trust in the digital economy, Mr Batch says.

“Across industr[ies] we have seen a lack of maturity in the consent space, such that any updates to Australian law would require significant industry changes and uplift.”

Deloitte recommends five key actions brands can take to improve consent practices:

1. Have a smart consent strategy
2. Gain a deep understanding of your data, where it came from and what it is being used for
3. Don’t bundle certain consents
4. Create an online portal for consumers to monitor and change their consents.
5. Give more than two choices in cookie consent banners and avoid an “all-or-nothing" approach.