Medical Source Statements (MSS): What They Are and When You Need One

When you apply for disability, the Social Security Administration (SSA) will talk to your doctors about your medical history. This helps the SSA understand the severity of your conditions and what kind of work you might be able to perform. One piece of paperwork you can submit to confirm your medical limitations is a medical source statement (MSS).

What is a medical source statement?

A medical source statement (MSS) is a written document where your doctor shares:

• Their diagnosis of your condition

• Their opinion of its severity

• Their opinion on your ability to work because of your condition

The MSS will also talk about your treatments and your medical history. While this document isn’t required to apply for disability benefits, it can be helpful. You can submit as many statements as you’d like from doctors who treat you — like your primary care physician, a specialist, or any other medical professional.

Remember, your doctor can’t put you on disability. To get disability benefits, you have to apply through the Social Security Administration (SSA). But your doctor can be a big help with certain parts of the process, such as submitting a medical source statement to help prove your condition is severe.

Who needs a medical source statement?

Medical source statements are helpful for anyone whose doctor knows about your condition and your inability to work. However, there are some people who might benefit extra from an MSS, including:

- Anyone under the age of 50. This is because it’s harder to qualify for disability than it is for people over 50.

- People applying with only a mental health condition. It’s also more difficult to qualify for disability if you have only a mental health condition (and no additional physical health condition). Again, this is especially true for people under 50.

How important is the medical source statement?

A medical source statement is an important piece of documentation that helps build your case for disability. This statement is a way to prove that you’re as sick as you’re claiming you are.

After you submit an MSS, it goes into your file. Then it will be shared with any of the SSA’s medical examiners or judges that you see while continuing the application process. 

How do I get a medical source statement?

You can get a medical source statement by asking your doctor to write one. For best results, ask a doctor who you’ve been seeing for at least three months — someone who is aware that you’re applying for disability. This ensures they’ll be familiar enough with your condition and your case to write a strong statement. 

It’s also helpful to touch base with their receptionist or office clerk, since some offices might have an official procedure. Others may ask you for a form from the SSA that they can fill out.

If you have a disability lawyer, they will talk to your doctor(s) and help you get statements. The SSA also might reach out to your doctor during the review process to ask for a medical statement. 

Medical source statement form

You don’t need any one specific form for a medical statement. As long as your doctor includes all relevant information, that will be enough.

However, if your doctor asks you for a form, direct them to these examples from the SSA:

- MSS for physical conditions. This form asks questions about how well or for how long you can perform certain activities, like kneeling, walking, or operating foot controls. 

- MSS form for mental conditions. This form asks about your ability to do things like interact with coworkers or carry out instructions. 

5 tips for improving your medical source statement

A medical source statement is a valuable way to help prove your case — showing that you need disability benefits, and explaining why. This statement is an important opportunity to explain to the SSA how sick you are. So it’s essential for your MSS to be as strong as possible. 

1. One way to do this is by building a good relationship with your doctor. Make sure they know ahead of time that you’re applying for disability benefits. If you don’t have a doctor nearby who knows you well, it may be worth driving home to see a doctor who’s more familiar with your case. 

2. Whoever you decide to see for your MSS, continue seeing your doctor for several months. This will show the SSA you’re serious about getting treatment, but still aren’t getting better.

3. Be honest with your doctor every time you see them. If they don’t know about all of your symptoms and how those symptoms affect your life, they won’t be able to write about them — and the MSS won’t be as helpful.

4. If you want your doctor to say something specific about your condition (for example, that you can’t lift a certain amount of weight), make sure you’ve mentioned this to them before. Don’t ask them to add things they aren’t aware of. 

5. Finally, this should go without saying — but never ask your doctor to lie for you (and don’t lie on your disability application). The information your doctor knows about you should be consistent with what you’ve said in your application, including in the function report.

Where to get help with your disability claim

Getting disability benefits is a complicated process. It takes many steps and lots of paperwork, including a medical source statement.

That’s where a disability lawyer can help. People who apply for disability with a lawyer are three times more likely to win benefits.

We can help you understand if you have a strong case for disability. We’ll also match you with a qualified lawyer if you want one. Start here with our disability benefits quiz.