It's the one table at your wedding holding actual cash, and usually nobody is watching it.
200 weddings, 17 as a bridesmaid, and one of my own.
This is a chain of custody, not a chore.

The photographer owns photos. The DJ owns music. The caterer owns food. The gift table owns nothing and nobody, because it isn't a vendor and it isn't a moment. It just quietly fills up with envelopes all night while every single person you trust is busy doing something else.
And it is the only table at your wedding with money on it. Not metaphorically. Actual cash, in envelopes, unattended, in a room a stranger can walk into. Wedding-gift theft is common enough that venues warn couples about it, and the numbers in the news are not small — one California couple lost a box holding tens of thousands in cash and checks, taken during their own reception.
You do not need to be frightened about this. You need to have decided it in advance, which takes about four minutes.
Not one person, and not "someone will grab it." The envelopes move through the night, so the job moves too.
Pick: Whoever is already stationed near the entrance — a greeter, an usher, or the venue's own staff if they offer.
If nobody owns it: The box sits unattended in the room closest to the door, which is exactly where a stranger walks in and leaves with it.
Pick: One trusted adult who is NOT in the wedding party and will not be drinking heavily.
If nobody owns it: Nobody notices the box is gone until the end of the night, by which point nobody can say when it left.
Pick: Someone sober who is staying until the very end. Usually a parent or a sibling.
If nobody owns it: Gifts get loaded into three different cars, or left in a corner for the cleaning crew.
Pick: The person whose home or hotel room the gifts sleep in. Say the address out loud.
If nobody owns it: Everything sits in a car boot in a hotel car park overnight, which is where the second theft happens.
Most card boxes are decorative and open-topped, because they were chosen to look nice in photographs. A pretty box with an open top is a bowl of cash.
Use a box with a real lock and a narrow slot
Slot narrow enough that a hand cannot reach in. If it looks like a post box, it is right. If it looks like a basket, it is not.
Bolt, weight or tether it
The most common theft is not picking envelopes out — it is picking the whole box up and walking. A box that cannot be carried casually is most of the defence.
Put it where staff stand, not where guests arrive
You + venueDecide the exact spot at the walkthrough.
Near the bar or the DJ, in a sightline. The entrance table is the worst place: closest to the door, and unmanned once guests are seated.
Empty it at least once, mid-reception
Card box holderQuietly, into a bag that leaves the room.
Even if the box goes, half the night is already safe. This single step is the difference between a bad story and a catastrophe.
Almost every gift story I know is a handoff failure, not a theft. Two people each thought the other had it. A car got loaded and a bag stayed on a chair. Someone took the cards home and nobody knew whose house they were in for three days.
Do the handoff before the send-off, not after. After the send-off you are gone, the room is emptying, and the people who know the plan have started saying goodbye.
You will not remember. Twenty envelopes in, the names blur, and a fortnight later you are holding a cheque with no idea which card it came in.
The Gift Tracker in the kit is built for exactly this, and there's an editable spreadsheet version if you'd rather work on your phone.
It's the only table at your wedding with money on it. Give it a name.
Ctrl+P / Cmd+P. Give it to whoever is taking the box home.