Short answer — the most popular instant coffee brands (U.S. market and globally) are:

1. Nescafé (Nescafé Classic, Taster’s Choice, Nescafé Gold). Nescafé is the largest instant‑coffee brand worldwide and a market leader in many countries. (finance.yahoo.com)
2. Starbucks VIA (instant microground packets). Widely used in the premium instant segment in the U.S. and sold through Starbucks’ channels. (ai-smarties.com)
3. Folgers (instant varieties) — a top mainstream U.S. household brand. (ai-smarties.com)
4. Maxwell House (instant) — another long‑standing mainstream U.S. brand. (grandviewresearch.com)
5. JDE Peet’s / Jacobs, Kenco, Douwe Egberts — big players in Europe and growing in global instant coffee offerings. (industryresearch.biz)
6. Regional/value & 3‑in‑1 winners: brands like Vietnam’s Trung Nguyen G7 (popular for 3‑in‑1 sachets), various supermarket private labels, and specialty instant startups (freeze‑dried premium options). (finance.yahoo.com)

Why these are “most popular”

• Nescafé (Nestlé) consistently posts the largest instant‑coffee sales globally and strong household penetration. (finance.yahoo.com)
• In the U.S., mainstream legacy brands (Folgers, Maxwell House) plus Starbucks’ VIA occupy the biggest retail/consumer mindshare. Market reports show jars and single‑serve sachets are the dominant packaging formats. (grandviewresearch.com)

If you want, I can:

• Give a short buying guide (best for taste, best value, best premium instant), or
• Show best‑selling instant products on Amazon/major retailers right now (I can fetch current top‑seller lists).