The best running underwear and period pants for women

# Overview Choosing the right underwear for running affects comfort more than many runners expect. Everyday cotton underwear tends to hold sweat, increase friction and can lead to chafing or moisture-related irritation. Women's Running testers recommend technical fabrics, minimal seams and styles that match your personal fit preferences and the type of run you do.

# Best picks by style The testers named go-to options across common styles. For each, they noted fit, fabric behaviour and wash durability.

• Best full brief: Runderwear Women's Running Briefs — praised for high waist coverage, long-distance comfort and durability in the wash.
• Best bikini: Reebok Suki Briefs — seamless, no visible panty line under tight leggings, soft to the touch and strong value for money.
• Best high-waist brief: BAM Seamless High-Waist Brief — bamboo fabric that testers described as very soft with generous bum coverage and good stretch.
• Best lightweight thong: Reebok Rae Bonded Thong — chosen when minimal fabric is preferred to avoid show-through and excess material under leggings.
• Comfiest thong: Universal Performance Seamless Bamboo Thong — highlighted for comfort.
• Best bamboo thong: Step One SmoothFit Thong — a bamboo option for those wanting that fabric.

# Period and leak-proof options for runners Testers separated period pants into sport-focused and higher-absorbency choices so runners can match protection to flow and activity.

• Most lightweight: NIXI Body Coni Sporty — aimed at runners who want a lighter, sportier period option.
• Best for heavy flow: WUKA Ultimate Midi Brief — recommended for greater absorbency during heavier days.
• Best bamboo option: Step One Period Full Briefs — bamboo fabric for comfort with period protection.
• Best thong style: WUKA stretch thong — for those who want thong shape with leak protection.
• Best bikini style: Modibodi Seamfree Bikini — a leakproof bikini cut.
• Best boxer style: NIXI Body The Anne Leakproof Boxer Brief — a boxer option for coverage and leak security.

# Buying guide: practical criteria to use Choose running underwear using these concrete factors:

• Seams: look for minimal or bonded seams to limit rubbing during repetitive motion.

• Durability: consider how well the garment holds shape and colour after washing. Testers noted some higher-cost items lasted well enough to offset price.

# Tester notes and practical tips Testers repeatedly highlighted two practical outcomes: chafe-free long runs and garments that wash well. One tester called the Runderwear briefs the "best running pants ever" for long-distance use without chafing. The Reebok Suki Briefs earned praise for seamless construction and reliable sizing for gym and running use. Bamboo options were recommended when softness and stretch are priorities.

# Quick decisions If you want minimal visibility under leggings, start with the Reebok Rae Bonded Thong or Reebok Suki Briefs. For long-run security and coverage, try Runderwear briefs or a high-waist bamboo brief. If you need menstrual protection, select a sport-oriented period pant for lighter days and a higher-absorbency brief for heavier flow.