Yes, you will have to add all contributions together as one. And yes generally the max contribution is $6,500 in 2018 if you are over 50 years old.
From IRS Retirement Topics - IRA Contribution Limits:
For 2018, your total contributions to all of your traditional and Roth IRAs cannot be more than:
- $5,500 ($6,500 if you’re age 50 or older), or
- your taxable compensation for the year, if your compensation was less than this dollar limit.
But your Roth IRA contribution might be limited based on your filing status and income. See 2018 - Amount of Roth IRA Contributions You Can Make for 2018 for details.
