Online invitations are priced four ways: free, usually with ads or the service's branding on them; per guest; by subscription; or a flat fee per event. Which one is cheapest for you comes down to one number: how many people you are inviting.
Say you are inviting thirty guests to a seventh birthday. If a service charges per guest, your bill is its per-guest rate times thirty. Then two classmates you forgot and three cousins get added, and the bill is the rate times thirty-five. Under a flat fee, thirty guests and thirty-five cost exactly the same, and so would sixty.
To find the break-even point, divide the flat fee by the per-guest rate. If your guest list is longer than the result, the flat fee is cheaper. If it is shorter, per-guest pricing wins. With credits, do one extra step first and turn the credits into dollars for your actual list, because the real price is hard to see until you do.
For a barbecue, a playdate or dinner with friends, a free invitation or a plain text message is all you need, and paying for more would be silly. Before you choose a free service for something bigger, open the invite as a guest would. See what surrounds your party details, and check whether RSVP tracking is part of the free tier or sits behind an upgrade.
Blast, which publishes this guide, is in this group: an animated video invitation with music, sent as a link, free to create and send, with unlimited guests and no subscription.
A short, fixed list is where it shines: eight friends at a sleepover, a dinner for twelve. The risk is a list that grows. Ask what happens when you add people after sending, since that is exactly when hosts discover the second charge.
If you send invitations all year, for a club, a school group or a business, a subscription lowers the cost of each one. For a single party it rarely fits. You pay for months you don't use and have to remember to cancel. Check, too, whether your invite and guest list stay available once the subscription ends.
One event with a long or uncertain guest list. A whole class plus siblings, a baby shower where both families keep adding names, a quinceañera with relatives in three countries: in each case you know the cost before you know the count. The honest downside is the mirror image. For a handful of guests, a flat fee can cost more than a per-guest plan, and it always costs more than free.
Headline prices hide things. These questions bring them out, and they are worth asking of every service, including the free ones.
Many are, with a trade-off. Free invitations often show ads or the service's branding, and nicer designs or features may sit behind a paid tier. Open the invite as a guest would before you send it to everyone.
Usually not. A subscription pays off when you send invitations often. For one event, a free option, per-guest pricing or a flat fee is simpler, and there is nothing to cancel afterward.
For most guest lists, yes, because printed invitations add a card, an envelope and a stamp for every guest. For a very short list the gap is small, and paper may be worth it for the keepsake.
No. Blast is free to create and send, with unlimited guests and no subscription, so you can keep sharing the same link as the list grows.