Geriatric assessment (GA) for older patients with lung cancer could provide insight into vulnerability, cognitive impairment, and risk of toxicity. Discontinuation and complications of intensive treatment could potentially be prevented in vulnerable and frail patients. This study aimed to evaluate current clinical practice of GA for older patients with lung cancer in the Netherlands and identify potential hurdles for implementation. Pulmonologists and radiation oncologists participating in the NVALT25-ELDAPT trial completed an online questionnaire regarding current practice of GA, added value of GA for treatment decision-making and logistic barriers for patients with non-small cell lung cancer. 15 out of 17 centers responded. Three performed GA as standard procedure, three on indication, eight considered a frailty screening step before GA, and one did not perform GA. Suspicion of cognitive problems was mentioned most often as indication for GA and of added value for treatment decision-making, followed by older age, curative-intent treatment, and stage I-III lung cancer. Administered instruments for screening and extensive GA were diverse. Main barriers to implement GA in clinical practice were logistic problems (timescales and availability of trained personnel). The use of GA in clinical practice for patients with lung cancer varied widely across centers regarding instruments and domains. Physicians are uniform in their opinion about indications for GA and the added value for treatment decision-making. Research should focus on manageable instruments and important domains to assess for this heterogeneous group of older patients with lung cancer to optimize treatment selection. Trial registration The NVALT25-ELDAPT trial is registered under trial number NCT02284308. Details are available at http://www.eldapt.org (predominantly in Dutch).