Purpose Immunotherapy-based approaches are standard first-line treatments for advanced/metastatic lung cancer or for chemoradiotherapy consolidation in locally advanced disease. Uncertainty on how to treat patients at disease progression prompted us to develop a consensus document on post-immunotherapy options in Spain for patients with advanced wildtype lung adenocarcinoma. Methods After extensive literature review, a 5-member scientific committee generated 33 statements in 4 domains: general aspects (n = 4); post-durvalumab in locally advanced disease (n = 6); post-first-line immunotherapy ± chemotherapy in advanced/metastatic disease (n = 11); and post-first-line platinum-based chemotherapy in advanced/metastatic disease (n = 12). A panel of 26 lung cancer experts completed 2 Delphi iterations through an online platform rating their degree of agreement/disagreement (first-round scale 1-5 and second-round scale 1-4, 1 = strongly disagree, 4/5 = strongly agree) for each statement. Second-round consensus: ≥ 70% of responses were in categories 1/2 (disagreement) or 3/4 (agreement). Results Consensus was reached for 2/33 statements in the first Delphi round and in 29/31 statements in the second round. Important variables informing treatment at disease progression with an immunotherapy-based treatment include: disease aggressiveness, previous treatment, accumulated toxicity, progression-free interval, PD-L1 expression, and tumour mutational burden. A platinum-based chemotherapy should follow a first-line immunotherapy treatment without chemotherapy. Treatment with docetaxel + nintedanib may be appropriate post-durvalumab in refractory patients or following progression to first-line chemotherapy + immunotherapy, or second-line chemotherapy after first-line immunotherapy, or first-line chemotherapy in some patients with low/negative PD-L1 expression, or second-line immunotherapy after first-line chemotherapy. Conclusions To support decision making following progression to immunotherapy-based treatment in patients with advanced wild-type lung adenocarcinoma, a consensus document has been developed.