A Slow Reply Is Not Automatically a Rejection
People have different relationships with their phones. Work, sleep, family responsibilities and personal habits can all affect response time. One delayed message tells you very little by itself.
Look at His Normal Pattern
The useful question is whether this is normal for him. If he has always replied slowly but continues conversations warmly, that is different from someone who suddenly becomes distant after previously communicating consistently.

Notice What Happens When He Does Reply
Does he answer your question? Ask something back? Continue the conversation? Make plans? Effort after the delay can tell you more than the delay itself.
When Slow Replies Can Signal a Problem
A sudden drop in effort, one-word responses, repeated cancellations and never initiating contact can form a pattern that deserves attention. Do not reduce the whole situation to a number of hours.
How to Respond Without Losing Your Peace
Avoid sending multiple anxious messages simply to force a response. Continue your day. If the pattern genuinely bothers you, explain what communication rhythm works for you and ask what works for him.

Set a Healthy Texting Rhythm
Dating does not require identical texting habits. The goal is an arrangement where both people feel respected. Some couples communicate more through calls or in-person time than constant messaging.
Frequently Asked Questions
Is it normal for a man to take hours to reply if he likes you?
Yes. Response time alone cannot establish interest.

Should I double text?
One normal follow-up is fine when there is something useful to add. Repeated anxious follow-ups usually do not help.
How long is too long?
There is no universal number. A sudden change in an established pattern matters more.
Final Thoughts
A quiet phone can trigger a lot of assumptions. Before deciding what a delayed reply means, look at the broader pattern of effort, communication and behavior.