As the paper sits, it can compress and become a dense, papier-mâché-like plug. Once it loses its air pockets and hardens, it becomes much more difficult to remove with a standard plunger.
Ultimately, while the chemistry of toilet paper suggests that a clog will eventually dissolve, relying on this process is a gamble with poor odds. The plumbing systems in modern homes are designed for flow, not stagnation, and the time required for a passive dissolution often exceeds the convenience of the household. The biological and chemical reality is that the paper will break down, but the structural reality of plumbing means that waiting is often a precursor to a worse blockage. Therefore, while the science offers a glimmer of hope, the practical answer remains firm: the plunger is, and likely always will be, faster than the chemical reaction.
While the paper will technically break down over time, leaving a clog sitting in your pipes is risky for two main reasons:
If your clog involves "flushable" wipes, it will dissolve on its own. These products are often made of synthetic materials or reinforced fibers that can remain intact in a sewer system for years. If wipes are the culprit, you will need a plunger or a plumbing snake to physical remove the blockage.
Hot water moves molecules faster and can help break down the fibers more quickly than cold water.
A clogged pipe is a stagnant pipe. If anyone else in the house flushes a toilet or runs a sink, that water has nowhere to go but back up into your shower or onto the bathroom floor. How to Speed Up the Process
Pour a generous amount of liquid dish soap into the bowl. It acts as a lubricant for the pipes and helps water penetrate the paper fibers.
However, the "eventually" in that sentence is the primary variable. While toilet paper is designed to dissolve, it does not dissolve instantly. Standard toilet paper can take anywhere from a few minutes to nearly twenty minutes to break apart in agitated water. In a stagnant toilet bowl, where there is no current to help separate the fibers, this process can take significantly longer—hours, or in some cases, days. If the homeowner waits long enough, the paper will indeed turn into a mush that can be flushed away. The problem lies in the fact that "long enough" is rarely a practical timeframe for a household that needs to use the facilities.