Abstract Background: The early diagnosis of idiopathic pulmonary fibrosis (IPF) has become increasingly important due to evolving treatment options. IPF patients experience a significant delay in receiving an accurate diagnosis, thus delayed access to tertiary care is associated with higher mortality independently from disease severity. Objective: The aims were to evaluate whether there had been a delay in the referral process, and to determine whether the referring doctors had suspected IPF or other interstitial lung disease (ILD) already during the time of referral. Methods: Ninety-five referral letters of patients with IPF identified from the Finnish IPF registry were evaluated with respect to time of referral, referring unit, grounds for referral, symptoms, smoking status, occupational history, clinical examinations, co-morbidities, medication, radiological findings and lung function. Results: Fifty-nine percent of referral letters originated from primary public health care. The time from symptom onset to referral was reported in 60% of cases, mean time being 1.5 (0.8–2.3) (95% CI) years. The main reason for referral was a suspicion of interstitial lung disease (ILD) (63%); changes in chest X-ray were one reason for referring in 53% of cases. Lung auscultation was reported in 70% and inspiratory crackles in 52% of referral letters. Conclusions: Primary care doctors suspected lung fibrosis early in the course of disease. Lung auscultation and chest X-rays were the most common investigational abnormalities in the referrals. Providing general practitioners with more information of ILDs might shorten the delay from symptom onset to referral.