OUR STORY

Built By Collectors, For Collectors

As a small group of collectors, we faced a frustrating problem. Traditional grading services were expensive. Not just that, they also made us wait months and months to get our cards back.

We knew collectors deserved better. So, we built a better option right here in Michigan.

Built By Collectors, For Collectors

How We Grew
01
Starting Small
We took our time to get the process right. We graded over 10,000 cards for local collectors first.
02
Going National
Once we refined our processes, we opened our doors to collectors across the country.
03
Where We Are Now
By mid-2026, we proudly grade over 1,000 cards a week. Most importantly, we still enjoy every minute of the journey!

What We Offer Today
01
Fast Turnaround
You get your favorite collectibles back in weeks, not months.
02
Display-Ready Slabs
Our crystal-clear, durable holders protect your cards and look great on any shelf.
03
Michigan Roots
We operate locally with high standards and personal care for every single submission.

FAQ

What's different about Sigma Card Grading?

As a fully self-funded organization, we care foremost about keeping our promises. We've been personally burned by basement grading companies who don't prioritize customer experience or have the funds to keep afloat. We're committed to doing the right thing and doing it sustainably — for the love of the hobby.

Are you going to charge me based on the grade? What's included in the list price?

Absolutely not — the price you see is the price you pay. We'll never hit you with an upcharge based on your grade because we think that's crazy.

For as low as $5 per card, you get:

  • AI supported, human verified grading
  • Your card preserved in a beautiful, ultrasonic welded slab
  • Return shipping to you in the continental US at no additional cost
What kinds of cards do you grade?

Sigma focuses on grading standard size (35pt–130pt) cards — sports, Pokémon TCG, Magic the Gathering, and more — with a maximum recommended value of $250 per card. We've recently expanded to support standard size cards up to 180pt with our Thick Slab Upgrade. Tobacco cards are placed in BCW Tobacco Insert Sleeves prior to placing.

At this time, Sigma does not provide autograph authentication or accommodate non-standard sizing or high-value cards. If you need help estimating your cards' value before submission, we recommend Card Ladder or PriceCharting.

What happens after I pay?
  1. You'll be emailed instructions on prepping your cards for shipment. More details can also be found on our Submission Instructions page.
  2. You ship your cards to Sigma Card Grading, 901 S. Bridge St. #256, Dewitt, MI 48820.
  3. Within about 10 days, your graded cards are shipped back to you, with free return shipping!
How should I package my cards for shipping?

It's important to pack your cards the right way to ensure they make it to Sigma safely. Always begin by placing each card in a penny sleeve and then into a top loader or card saver.

We also recommend placing stacks of up to 25 cards sandwiched between two pieces of cardboard and bound with a rubber band or painter's tape — held firm without being tight enough to cause damage. Add your stacks to a cardboard box or bubble mailer and send it our way!

Should I choose you over PSA/CGC/TAG...etc?

That depends. If you have rare, highly valuable cards, or you're looking for the autograph authentication that others provide, we're probably not the best choice for you.

However, if you're looking for quality, accurate grading services at affordable prices — and getting your cards back in your hands quickly — we're tough to beat.