Office supplies are generally considered a variable cost. This is because their total expense can fluctuate depending on the level of business activity. For instance, if a company has a higher volume of sales or projects, it will typically consume more office supplies, which means that costs increase with usage.
In contrast, fixed costs remain constant regardless of business activity levels, such as rent or salaries. Since office supplies are usually ordered and used according to specific needs and usage can vary from month to month, categorizing them as a variable cost is appropriate.