How can I tell my boss how stressed I am without it sounding like I'm incapable of doing my job?

I have faced this myself and I dealt with it by putting it into a positive frame of reference. Rather than approaching it from the perspective of "I can't cope with this workload!", I framed it as the following and sent via an email so I didn't trip over my words, "At the moment, I am getting a lot of ad hoc jobs coming through that are affecting my ability to give my absolute best with my regular tasks. Can I defer my regular tasks until next week to allow me to get these ad hoc jobs out of the way?" By approaching it in this manner, I was projecting a constructive attitude, which was received by my manager in a positive manner. The objective of the exercise for me was to express how great my work stress was while coming across as positive and constructive.

You can tell your boss that you need some time off. Take a couple of weeks of vacation or FMLA, and use the time to assess what is occurring with your job, and if you need to speak to your boss, adjust your attitude, or quit. Does that sound reasonable?

Remember, your boss is not necessarily your friend. It may be best to focus on feelings as opposed to behaviors. Stress is a feeling. Instead, focus on the source of the stress. Play the game by telling your boss what they want to hear while still communicating your difficulty. For example, "I really want to a good job here, but I'm having a hard time managing the workload. I can see it's going to be a problem soon, so I just wondered if you have any strategies for helping me manage this." That way, you are letting your boss know, and at the same time, you're stepping up, taking responsibility, being proactive AND stroking their ego by asking for advice--all things bosses love. That will be much more effective in getting your bosses' support than simply saying, "I'm super stressed out. This is unfair and I can't do it anymore." There is a time and a place to state your feelings, especially if you feel something is really unfair, but pick those battles very carefully, because if you lose, it could mean you need to find another job. Good luck.

Reach out, especially if you feel your boss or colleagues are supportive and understanding. Chances are you're not the only one. It can help to paint support as a team need and to offer ideas of how your team can work together to overcome this. It depends too on why you are stressed. In our work site, we have a lot of people stress, so having potlucks and fun gatherings helps a lot. In a site like production work, productivity or safety may be the reasons for stress. Still, helping your employer to help you actually could be a way of helping the team and painting how you can contribute to the company at a higher level in the event that you are hoping to be promoted in the long term as well.

It is important that you mention that you find certain aspects of the job to be too much. When I was promoted to assistant manager, I found that it was too stressful for me and so I told them I wanted to simply go back to my original job. They allowed this without thinking any less of me. You will not sound incapable, just ensure that you mention particular things that you find to be too much and see what they can do. Maybe they will offer you a few tips on how to go about certain tasks, which you will find more useful. Better that you talk to them though.

If you are stressed because a lot of work is in your hands, it is better to tell your boss that you are able to do a better quality job when there is not as much load as there is and that quality over quantity is what you strive to achieve

Tell him/her that you would love to move further in your job but it's hard to do so when you are stressed from said job. Remember confidence and honesty is always the best, and don't forget to be assertive! :)

I am fortunate enough that I have a very good relationship with my boss and can just have the conversation. For those that don't have that kind of relationship, I suggest going in with a game plan. Maybe make a list of the reasons why you are stressed, that way you don't forget anything when sitting down with your boss. Also, come up with a plan to manage or reduce that stress. This way, if the boss asks about it, you are prepared. Hopefully, they will respond favorably if you show that you have tried stradegies instead of just "complianing". Also, if the stress is related to another person slacking off, you might want to address it with them before going over their head.

I've never really had a boss that I can tell that I'm stressed, except for one. A good way to word it is that you can ask if they have input on how you can manage your time better with the tasks they're given, because you DON'T want to overwhelm yourself. Even if you are overwhelmed, it looks like you're so invested that you're seeking advice on how you can improve to meet organisational goals.

Try to frame the discussion in a way that focuses on the work, not how you feel. Assume that you have a hard limit of X amount of time to do that work. Make a priority list of the things that will and will not get accomplished during the next month based on your time limit. Then this simply becomes a discussion about priorities. You give them the chance to choose what work does not get completed based on your capacity. Your boss is probably already worried about you becoming burned out and leaving. That's not good for anyone.