Wedding gift etiquette used to be a set of strict rules and now it's a set of quiet questions: is cash okay, how much is enough, how long do I actually have, and is anyone really checking? The honest answer is that the rules relaxed, and what's left is mostly about not making the couple feel awkward.
Here's the modern version, from both sides of the gift.
Cash or registry?
Both are completely fine now. The registry is the couple telling you exactly what they want, so using it is always correct. Cash is equally welcome, and often preferred, because most couples marrying today already have the household and would rather put money towards a honeymoon or a house.
The only real rule is to follow what the couple set up. If there's a registry or a cash fund, use it, it's the answer they already gave you.
How much to spend
There's no fixed number, and anyone who tells you there is is guessing. The useful guide is the relationship: $50 to $75 for a coworker or distant friend, $100 to $150 for a good friend or relative, $150 to $200 for a close friend or sibling, and more for immediate family. Scale it down if travel was expensive, and never give more than you can genuinely afford.
When to send it
The traditional window is up to a year after the wedding, and it still stands. Sending before the wedding is kindest, especially cash, because the couple aren't then carrying envelopes home at midnight. But a late gift is always better than no gift, and nobody is actually keeping the calendar.
The thank-you note timeline
This is the rule that actually matters. Thank-you notes should go out within about three months of the wedding, and each one should name the specific gift, not a generic 'thanks for the present'. A late, specific note beats a prompt, vague one, and a handwritten card still beats an email for anything above a small amount.
If you're the couple, the trick is to write them as gifts arrive rather than in one marathon after the honeymoon. Five minutes a week beats a weekend of writer's cramp.
For couples: wording the ask politely
If you'd rather have contributions than a traditional list, say so warmly and once: 'Your presence is the only present we need, but if you'd like to give something, a contribution to our honeymoon would mean the world.' Then point to the registry.
The first half is what makes it land. Guests want to feel wanted, not billed, and that one clause is the whole difference.