Objectives: Travel restrictions is an often-used tool for governments to prevent the spread of COVID-19. Methods: We here used a simple simulation model to investigate the potential effects of travel restrictions within a country. Results: We found that travel restrictions can delay the peak of the epidemic considerably, but do not affect the spread within the country. We also investigated the effect of implementing travel restrictions early or later in the epidemic, and found that fast implementation is crucial for delaying the epidemic. Conclusions: Fast implementation of travel restrictions is crucial for delaying the peak of a subsequent outbreak of COVID-19 within a country.