Background: Little is known about the factors associated with treatment in patients diagnosed with metastatic cancers and who die soon after diagnosis. We examined patterns of treatment in patients diagnosed with metastatic lung, colorectal, breast, and pancreatic cancer who died within one month of diagnosis. Methods: Using the National Cancer Data Base, we identified de novo stage IV lung, colorectal, breast, and pancreatic cancer patients ages ≥18 years and diagnosed between 2004-2014 who died within one month of diagnosis. We used descriptive analyses to calculate percentages and multivariable logistic regression analyses to generate adjusted odds ratios for receipt of specific types of treatment. Results: Among 97,884 patients, 66% had lung, 18% pancreatic, 12% colorectal, and 3.7% breast cancer. Surgery was least common in pancreatic (0.4%) and most common in colorectal (28.8%) cancer. Rates of chemotherapy ranged from 5.8% in colorectal to 11.3% in lung and breast cancer. Rates of radiation ranged from 1.2% in pancreatic to 18.7% in lung cancer. Endocrine therapy was initiated for 23.7% of patients with hormone receptor-positive breast cancer. Over the study period, surgery for colorectal and breast cancer, chemotherapy and radiation treatment for lung cancer, and chemotherapy for breast and pancreatic cancer progressively declined (P trend < 0.01). Age, insurance, and facility type were strongly associated with receipt of treatment across most cancer types. Uninsured patients had 43% lower odds of receiving surgery for colorectal cancer, 34% lower odds of initiating chemotherapy for lung cancer, and 47% lower odds of initiating chemotherapy for breast cancer compared with their privately insured counterparts. Compared with patients with lung cancer treated at NCI-designated cancer centers, those treated at community cancer centers had 48% lower odds of initiating radiation. Conclusions: Treatment of patients diagnosed with imminently fatal metastatic cancer (death within one month of diagnosis) varied markedly by cancer type and patient/facility characteristics. More research is needed to identify patients with imminently fatal metastatic cancer who would benefit from early treatment.