Background The use of nicotine products among youth is rising, while existing cessation services remain underutilized. Thus, the U-Niko intervention was developed to provide an evidence-based, youth-oriented approach to effective nicotine cessation.

Methods A two-arm cluster randomized controlled trial will be conducted among youth aged 16-25 in 55 municipalities in Denmark. Using the online randomization program Sealed Envelope, we conducted a blinded stratified randomization of 55 Danish municipalities resulting in 27 municipalities in the U-Niko intervention group and 28 municipalities in the control group (tobacco and nicotine cessation recruitment and counseling as usual). The primary outcomes measure the effectiveness of all three focus areas in the intervention group compared to the control group: A) the municipal counselors’ self-efficacy in youth cessation counseling, B) the number of recruited youths for cessation counseling, and C) the self-reported 14-day point prevalence abstinence of youth at six months follow-up. Secondary outcomes are the number of recruited youths in a municipality compared to the previous year, continuous abstinence, and validated 14-day point prevalence abstinence at six months follow-up.

Discussion By evaluating all three focus areas of the U-Niko intervention, this study aims to provide robust evidence for improving youth cessation interventions at a local and national level.

Trial registration The study was registered in ANZCTR (ACTRN12624001470583) on 18/12/2024. The Universal Trial Number is U1111-13-14-6117.

The authors have declared no competing interest.

The study was registered in ANZCTR (ACTRN12624001470583) on 18/12/2024. The Universal Trial Number is U1111-13-14-6117.

Yes

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study is approved by the Danish National Scientific Ethics Committee (F-24044815).

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

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No datasets were generated or analysed during the current study. All relevant data from this study will be made available upon study completion.