PurposeThe aim of this paper is to examine the temporal sequencing of methamphetamine use and the onset of mental health problems among a sample of dependent methamphetamine users.Design/methodology/approachThe study used a self‐reported timeline method to examine the sequencing of first use, regular use and problematic use of methamphetamine and mental health issues among 126 users with lifetime dependence.FindingsThe majority of the sample (69 per cent) reported previous mental health diagnosis or treatment. Of this sample, 22 per cent reported mental health problems prior to their first use of methamphetamine and 72 per cent reported mental health problems after first use of methamphetamine (with the rest around the same time or unsure). On the timeline, mental health symptoms were first indicated around a year after first regular use of methamphetamine and around the same time as problematic use. Respondents identified a lag time of five years between first problematic use of methamphetamine and seeking treatment for methamphetamine‐related problems, but those that received mental health treatment engaged in methamphetamine treatment earlier.Practical implicationsAmong this sample, mental health problems coincided with problematic methamphetamine use (rather than any use) suggesting prevention efforts may be better directed at preventing transition to heavy use or use of potent forms or injecting, rather than directed at prevention of uptake. On this basis, stepped care might be appropriate for methamphetamine users.Originality/valueDespite a substantial research literature establishing the link between methamphetamine use and mental health problems, little is known about the order of onset and the implications of this for treatment. This is one of the few studies specifically investigating the temporal sequencing of methamphetamine use, mental health symptoms and treatment seeking among a sample of dependent methamphetamine users.