There are no hard and fast rules on the type of necklace you should pair with a particular style of belt, and an almost infinite number of workable combinations. But you do have to ensure that the two accessories aren’t in competition with each other.
The two main variables you have to play with are the contrast of the belt against your outfit and the length of the necklace. Here are two safe options (the principles apply to both waist-cinching and hip slung belts):
- Pair any belt with a short necklace: The belt can be any width and either low or high contrast against your outfit. With a short necklace (above the bust line), the two accessories are far enough apart that they don’t compete.
- Pair a low contrast belt with any length necklace: The belt can be any width, but when it’s low contrast against an outfit the necklace becomes the focal point so the two accessories live in harmony.
This is not to say that it’s impossible to make a long necklace work with a high contrast belt, but this combination is more risky and harder to get right.
Another problem arises, especially if you are short-waisted, when long necklaces touch your belt. I find that long necklaces clank against my belt when I sit down. It drives me batty so I only pair belts with short necklaces.
If you’re still doubt, leave off either the necklace or the belt. Or leave off the necklace and wear earrings.