Plavidian Mail Expert™
Your on-demand direct mail expert. Ask about tabbing, folds, piece sizes, postage eligibility, EDDM, or addressing and get a straight answer grounded in the USPS Domestic Mail Manual and the current Notice 123 price list. No sales call, no waiting on a rep.
Grounded
Answers from the DMM
Every answer is drawn from the USPS Domestic Mail Manual and the current Notice 123 price list loaded in our system, not from general knowledge.
Specific
Built for real pieces
Ask about the piece you are actually printing: a 6 x 9 card, a quarter-folded 11 x 17, a saddle-stitched booklet, an EDDM flat.
Honest
It says when it is unsure
If the standard for your shape is not on file, it says so and points you to a rep instead of guessing. Pricing always defers to the estimator.
Ask the Mail Expert™
Your On-Demand Direct Mail Expert
Final mailability and pricing are confirmed by USPS at acceptance.
Answering from the USPS Domestic Mail Manual effective 2026-07-12 (1,918 sections indexed) and USPS Notice 123 effective 2026-07-12. Prices come only from the imported Notice 123, never an estimate.
What people ask it
Question
Does an 8.5 x 11 tri-fold need tabs?
Yes. A tri-folded 8.5 x 11 self-mailer is letter-size and needs two non-perforated tabs on the top edge, with paper weight minimums that change above 1 ounce.
Question
Where can the address go on an 8.5 x 11?
Unfolded it mails as a flat, so the address goes in the top half of the piece and may run parallel or perpendicular to the short top edge.
Read the guides behind the answers
The Mail Expert answers from the same USPS standards we work to every day. Browse them directly.
USPS Mail Classes Explained
First-Class, Marketing Mail, Nonprofit, Bound Printed Matter, and Media Mail: what each class is for, what it can contain, and how to choose.
Postcard, Letter, Flat, or Parcel: USPS Size Limits
The exact dimensions that decide whether your piece prices as a postcard, letter, flat, or parcel, plus the nonmachinable surcharge list.
Folded Self-Mailers and Tabbing Requirements
How many tabs a folded self-mailer needs, where they go, fold orientation, paper weight minimums, and when tabbing does not apply.
Mailing Booklets: Size, Spine, and Tabbing Rules
How a bound booklet mails: letter versus flat thresholds, spine orientation, tab count by weight, and paper stock minimums.
Automation and Presort: How to Earn the Lowest Postage
What machinable, nonmachinable, and automation mean, the presort minimums, and the requirements that unlock the lowest per-piece prices.
Addressing, CASS, and Move Update Requirements
CASS processing, ZIP+4 and delivery point coding, the Move Update rule, and ancillary service endorsements for undeliverable mail.
Preparing a Mailing List
How to format a mailing list, why CASS and Move Update matter, deduplication and householding, and what drives the price your list qualifies for.
Designing Artwork That Mails Correctly
Address block placement, the barcode clear zone, indicia position, machinable aspect ratios, and where tabs and folds can and cannot go.
All mailing guides
Browse every USPS guide →