No, elective deferrals (including the catch up) are NOT allowed for a regular SEP (if you have an older SAR-SEP, those have different rules).  A SEP is limited to the 20% of net earning from self employment (after adjustments, it is less than 20% of your profit).

The "maximize" button seems to be maximizing a 401(k), which does allow elective deferrals (including the catch up).

Thanks you for the response.  Does that mean I could put the maximum into the SEP, and the remainder that is being shown could go into a Traditional IRA?  Or I can only maximize the SEP?

Thank you.

A Traditional IRA is limited to $6000 each ($7000 if you are age 50 or older).  Whether or not it is deductible or not depends on what your income is (a SEP is an employer plan, so that could limit it){.

https://www.irs.gov/retirement-plans/2019-ira-deduction-limits-effect-of-modified-agi-on-deduction-i...

If you are interested in larger retirement contributions for 2020, you may look into a 401(k) plan.

Ok, thank you.  So, since we each work for ourselves, it doesn't seem like a 401K is an option (I have ones from working at previous employers) - so did TurboTax get it wrong?  Sounds like you are saying max we can contribute (we are over 50) is the SEP max, and maybe $7K for Traditional IRA. Wondering what the $6K "make up contribution" as well as the $19K was all about.  

If you work for yourself, you certainly can set up a 401k.  Google "Solo 401k".

For some reason that 'maximize' button is including elective deferrals  and the 'catch up' amount as if you did have a Solo 401k.  I am pretty sure there is a button somewhere to maximize a SEP, but I'm not that familiar with how to find it in TurboTax.

Are you using the correct maximize button?    When you go through the Self-Employed Retirement Plans interview, the first section asks about Individual (Solo) or Roth IRAs.   If you say no to those, the next questions refer to Keogh, SEP and SIMPLE plans.   They each have their own maximize button, see image below.  

End of Year Retirement Tips for Employees and the Self-Employed