Wedding Invitation Size Guide: Standard Dimensions, Envelope Sizes & the Complete Stationery Suite
Wedding stationery guide · iCustomLabel.com
Every card dimension, every envelope size, paper weight explained, and the complete suite — so nothing gets ordered in the wrong size, nothing arrives in an envelope that doesn't fit, and nothing gets mailed at the wrong postage.
Wedding stationery sizing is one of the most practically important and least-romanticized parts of wedding planning. Get it right and everything flows — the invitation fits the envelope, the RSVP card fits its return envelope, the cardstock feels appropriate for the occasion, and nothing comes back from the post office. Get it wrong and you're reprinting 200 invitations three weeks before the wedding because the dimensions don't match the envelopes you already ordered.
This guide is the complete reference — every standard card size in the suite, the exact envelope dimensions that match each card, paper weight explained in plain terms, postage thresholds, and the specific dimensions of iCustomLabel's wedding stationery. Bookmark it and come back to it at each ordering stage.
Standard wedding invitation sizes
Standard wedding invitation sizes — the formats that work
Wedding invitations come in four broadly used size formats. Each has a distinct visual footprint and a slightly different effect on how the invitation feels in the hand. Here are the standard dimensions, from most to least common:
iCustomLabel's standard: iCustomLabel's save the date and wedding invitation cards are printed at 5×7 inches on 130-lb glossy cardstock — the industry-standard size that fits the A7 envelope, photographs beautifully, and works for every wedding aesthetic from rustic to formal. If you've ordered iCustomLabel invitations or save the dates, your cards are 5×7 and require A7 envelopes.
Visual size comparison
How wedding invitation sizes compare — scaled reference
3.5×5
RSVP
Postcard
Square
Square
★ Standard
iCustomLabel
Most popular
Formal
Formal
Large
Luxury
Proportional to each other. All scaled for display — not actual size.
Wedding envelope sizes
Wedding envelope sizes — what fits what
The critical rule for envelopes: the card should be ¼–⅜ inch smaller than the envelope in both dimensions to slide in and out easily without being loose enough to shift. An envelope that's too small creases the card; an envelope too large lets the card slide around and look sloppy.
| Envelope name | Envelope size | Fits this card size | Use for |
|---|---|---|---|
| A2 | 4⅜" × 5¾" | 4×5¼" card (or smaller) | RSVP response envelopes, small enclosure cards, thank you notes |
| A4 | 4¼" × 6¼" | 4×6" card | Postcard-style invitations (4×6), response cards, details cards |
| A6 | 4¾" × 6½" | 4½×6¼" card | Smaller invitations, bridal shower invitations, greeting cards |
| A7 | 5¼" × 7¼" | 5×7" card ★ Standard | The standard wedding invitation envelope — fits iCustomLabel's 5×7 cards perfectly |
| A8 | 5½" × 8⅛" | 5×7½" card or 5¼×8" card | Formal 5.5×8.5 invitations (with slight fold), large-format cards |
| A9 | 5¾" × 8¾" | 5.5×8.5" card | Formal half-letter invitations, 5.5×8 cards |
| Square 5¼×5¼ | 5¼" × 5¼" | 5×5" square card | Square invitations — requires non-machinable surcharge at USPS |
| #10 (Long) | 4⅛" × 9½" | 6×9" card (folded), letter-size folded | Large-format invitations requiring a fold, business-style formal letters |
Inner envelope vs. outer envelope
Traditional formal wedding invitations use a two-envelope system — an inner envelope (unsealed, listing the specific guests invited) nested inside a sealed outer envelope (with the guests' address). This tradition dates to the era when invitations were delivered by hand and the outer envelope was discarded upon delivery. In contemporary weddings, the two-envelope system is used primarily for very formal black-tie events; most modern weddings use a single outer envelope only.
If using a two-envelope system: the inner envelope is typically 1 size smaller than the outer envelope. The inner envelope for an A7 outer envelope would be approximately a 5×6⅞" inner envelope.
What size envelope for a 5×7 card
What size envelope fits a 5×7 card?
A 5×7 card fits an A7 envelope — which measures 5¼" × 7¼". The quarter-inch clearance on each side allows the card to slide in and out smoothly without bending or creasing. The A7 is the most widely available wedding envelope size and is stocked at most craft stores, paper suppliers, and online envelope retailers.
The standard wedding invitation envelope
Use for 4.5×6.25" cards only
But too loose — the card shifts. Use A7.
Buying A7 envelopes — what to know
- →Where to buy: A7 envelopes are available at Michaels, Hobby Lobby, Paper Source, Office Depot, and Amazon. Look specifically for "A7" not "5×7 envelopes" — the designation A7 ensures the exact sizing.
- →Paper finish options: A7 envelopes come in matte, textured (linen or cotton), and peel-and-seal or gummed flap options. Matte matches most printed invitations; linen adds a tactile luxury feel. Avoid glossy envelopes — they don't accept handwriting well.
- →Matching envelope color: White envelopes are standard. Ivory envelopes coordinate with warm-toned, formal invitations. Colored envelopes (navy, blush, sage) work with contemporary aesthetics. Match the envelope color to the invitation's primary background color, not the accent color.
- →How many to order: One envelope per invitation, plus 10–15% extra for addressing mistakes, damaged envelopes, and late additions to the guest list. Order extras before you need them — buying a second batch of the exact same envelope later is surprisingly difficult.
The complete wedding stationery suite
Every card in the wedding stationery suite — sizes, envelopes & order
A complete wedding stationery suite typically contains 4–8 pieces. Each piece has a standard size range and a matching envelope where applicable. Here's the complete reference:
| Card | Standard size | Envelope | Notes |
|---|---|---|---|
| Save the date | 5×7" | A7 (5¼×7¼") | iCustomLabel prints at 5×7". Mail 8–12 months before wedding. Some couples skip the envelope and mail as a postcard — requires postal approval and a slightly different design. |
| Main invitation | 5×7" (most common); also 5.5×8.5" formal | A7 for 5×7"; A9 for 5.5×8.5" | The anchor piece of the suite. Every other piece is sized relative to the main invitation. Mail 6–8 weeks before the wedding. |
| RSVP card | 3.5×5" or 4×6" | A2 (4⅜×5¾") for 3.5×5" A4 (4¼×6¼") for 4×6" |
Always include a pre-addressed, pre-stamped return envelope with the RSVP card. The RSVP envelope should be 1–2 sizes smaller than the invitation envelope — typically A2. |
| Details / information card | 3.5×5" or 4×6" (matches RSVP) | No envelope (included in main envelope) | Hotel accommodations, shuttle schedule, dress code, website URL. Keep the same size as the RSVP card for visual consistency — they nest inside the main envelope together. |
| Accommodations card | 3.5×5" or 4×6" | No envelope (included in main envelope) | Hotel block information, room rates, booking code. Optional if the information is on the wedding website — increasingly replaced by a website card that directs guests online. |
| Map or directions card | 4×6" or 5×7" | No envelope (included in main envelope) | Decreasing in use as GPS navigation has replaced printed directions. Still valued for destination weddings or venues in areas with poor cell service. |
| Inner envelope | Approximately 5×7" (slightly smaller than outer) | N/A — is itself an envelope | Used only in traditional formal suites. Unsealed, with guests' names written by hand. Significantly less common in contemporary weddings. |
| Outer mailing envelope | A7 for 5×7 suite; A9 for 5.5×8.5 suite | N/A — is itself the envelope | Contains the invitation, RSVP with its own envelope, and all enclosure cards. Address by hand or laser calligraphy on white or ivory. No return address sticker — a printed or embossed return address on the flap is standard for formal weddings. |
The nesting rule: Everything inside the outer envelope (RSVP card, RSVP return envelope, details card, accommodations card) should be the same size as each other — typically 3.5×5" or 4×6". Mixing card sizes inside the envelope creates visual chaos when the recipient opens it. Keep enclosure cards consistent with each other, even if they differ in size from the main invitation.
iCustomLabel wedding stationery — complete 5×7 suite
Paper weight guide
Wedding invitation paper weight — what the numbers mean
Paper weight in the US is measured in pounds (lb) using the bond or cover weight system. For wedding invitations, the relevant scale is cover weight — the weight measurement used for cardstock, business cards, and premium printed materials. Here's how to read the numbers:
Standard business card weight. Feels noticeably thin for a wedding invitation — guests will notice it flexes easily. Appropriate for inner cards (RSVP, details) where the lighter weight keeps the envelope from becoming too thick and heavy, but not recommended for the main invitation.
Solid, professional weight. Doesn't flex under normal handling. Appropriate for all wedding stationery — this is the minimum weight that reads as properly premium for a wedding invitation. Many standard invitation printers use this weight.
iCustomLabel's standard for wedding stationery. Noticeably heavier than 100 lb — substantial in the hand, resists bending under normal handling, and conveys quality immediately. This is the weight where guests remark on the quality of the paper. Recommended for main invitations and save the dates.
Luxury and letterpress invitation weight. Used for letterpress, foil-stamped, and high-end engraved invitations where the thickness is part of the tactile experience. Not necessary for digital printing — the weight advantage is primarily relevant for specialty printing techniques.
A note on "lb" vs "gsm": International paper weights are measured in grams per square meter (gsm). 130 lb cover = approximately 350 gsm. 100 lb cover = approximately 270 gsm. When comparing paper from US and international suppliers, use the gsm conversion to ensure you're comparing equivalent weights. Most US wedding invitation suppliers use lb; most European suppliers use gsm.
Wedding invitation postage
Wedding invitation postage — how to mail them without them coming back
Postage is the step that catches most couples off guard. Standard letter postage is calculated by weight and size — wedding invitations, which are heavier than a standard letter and sometimes non-machinable, frequently require additional postage. Underestimating postage results in invitations being returned to you or — worse — delivered postage-due to your guests.
Postage rules for wedding invitations
- →Always have a completed invitation suite weighed at the post office before purchasing postage for the full batch. Bring a fully assembled envelope — with the invitation, RSVP card and its envelope, and all enclosures inside — to your local USPS counter. They'll weigh it and tell you exactly what postage is required.
- →1 oz or less = one forever stamp. A single 5×7 invitation card in an A7 envelope with no enclosures typically weighs under 1 oz and requires one stamp. A full suite (invitation + RSVP + return envelope + 2 enclosure cards) often weighs 1.5–2.5 oz and requires additional postage.
- →Square envelopes require a non-machinable surcharge. If you're using square invitations (5×5") in square envelopes, USPS charges an additional non-machinable surcharge (approximately $0.40 as of 2025) on top of the regular first-class rate. Budget for this if using a square format.
- →Request hand-canceling at the post office. Ask the postal worker to hand-cancel rather than machine-cancel your invitations. Machine cancelers can damage decorative envelopes, embossed wax seals, and ribbon-tied suites. Hand-canceling adds a few cents per envelope at some locations; at others it's free.
- →Include return postage on RSVP envelopes. Pre-stamp every RSVP return envelope before including it in the invitation suite. Expecting guests to supply their own stamp dramatically reduces the RSVP return rate. A pre-stamped return envelope is one of the most practical things you can do for your guest experience.
- →Vintage stamps are a real option. USPS sells commemorative and vintage stamp collections that photograph beautifully on wedding invitation envelopes. Denominations can be combined — two lower-denomination stamps to reach the required postage often look more intentional than a single large-format stamp. Ask for "pretty stamps" or "floral stamps" at the postal counter.
Ordering tips
Wedding invitation ordering tips — avoid the most common mistakes
Before you place your order
- 1Finalize your guest list before ordering. Order exactly the number of invitations you need (one per household, not per guest), plus 10–15% extra. Reordering a second batch of 25 cards is significantly more expensive per-card than including 25 extras in the original order.
- 2Proofread everything three times. Invitations and save the dates with errors in names, dates, times, or addresses cannot be fixed after printing. Read every line — including the names, the venue name spelling, the website URL, and the RSVP date — before approving the proof. Have a second person read it who wasn't involved in creating it.
- 3Order invitations and envelopes from the same place if possible. Mismatched white tones (cool white vs. warm ivory) between the invitation and the envelope are one of the most visually apparent stationery mistakes. If ordering separately, compare physical paper swatches before committing.
- 4Build in more time than you think you need. Most couples underestimate the time required for addressing, assembling, and mailing invitations. Addressing 150 envelopes by hand takes 3–4 hours; assembling 150 complete suites takes another 2–3 hours. Add a week of buffer beyond your target mailing date.
- 5iCustomLabel's turnaround: Standard production at iCustomLabel is 1–3 business days plus shipping time. Rush production is available for same-day processing. For a destination wedding or any wedding where invitations need to mail 8+ months out, order at least 2–3 weeks before your target mailing date for comfortable buffer.
Custom 5×7 wedding invitations & save the dates — printed in Florida
iCustomLabel's wedding invitations and save the dates are printed at the industry-standard 5×7" size on 130-lb premium glossy cardstock — the weight that guests notice, the size that fits A7 envelopes, and the format that coordinates with every piece of your stationery suite. Personalized with your names, date, and design. Fast Florida turnaround.
Design your wedding invitationsFrequently asked questions
Wedding invitation sizes — quick answers
The most-searched questions about wedding invitation dimensions and envelopes, answered directly.
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