A common question is whether or not bread knives dull. It makes a lot of sense to ask this, as most knives do in-fact dull, but generally bread knives do not suffer the same fate. Most quality bread knives will last a long time without requiring any sharpening.
The main reason why bread knives last so long is because they have an extremely serrated edge, with lots of small teeth. These teeth create a sort of ‘saw’, where each tooth is pressed up against the material. Due to the combination of the many small teeth and the fact that bread is quite easy to cut, bread knives tend to last a long time, and often many, many years. The exception to this is if you purchased a knife of inferior quality, or if you used the bread knife to cut things other then bread.
If you eventually do want to sharpen your bread knife, you may find it hard to do so. The serrated teeth on a bread knife make it nearly impossible to use standard sharpening tools. You may find better luck with a ceramic sharpening rod, but since bread knives last so long, you may find it easier to simply buy a new one when your knife reaches the end of it’s lifespan.