Dan Sultan has cancelled the remainder of his solo tour after admitting to "inexcusable and disrespectful" behaviour at his most recent show.

The singer-songwriter apologised to fans on Monday and offered refunds to those who attended his Saturday performance in regional Queensland, after attendees accused the Australian musician of rambling and, at one point, falling off his stool.

On Tuesday, Sultan's manager confirmed the remainder of the Killer Solo Tour has been postponed.

"We apologise to Dan's fans for any inconvenience this may cause," the statement read. "Dan's health and wellbeing is our highest priority at this time and we thank you for your ongoing understanding and support.

"We hope to reschedule the postponed dates once Dan makes a full recovery. While we encourage fans to hold onto their tickets, which will be valid for entry to the rescheduled shows, the option to secure a refund is also available via the ticketing outlet or venue from which tickets were purchased."