# Low-fee propagation

Research: which sub-1 sat/vB transactions the Labs mempool keeps actually get mined, by which pools, and how long they wait.

URL: https://blockspace.wiki/research/low-fee-propagation/

**Status on [blockspacelabs.com](https://blockspacelabs.com): Research.**

## What it studies

The Labs site asks: "Which sub-1 sat/vB transactions our mempool keeps actually get mined, by which pools, and how long they wait."

The Labs node practises [sub-1 sat/vB relay](https://blockspace.wiki/glossary/sub-1-sat-vb-relay/): its [fee floor](https://blockspace.wiki/glossary/fee-floor/) is 0 sat/vB (as of block 972,320, 2026-10-20 12:17:53 UTC), so it keeps transactions that a node at Bitcoin Core's default floor of 1 sat/vB would refuse. Keeping a transaction in the [mempool](https://blockspace.wiki/glossary/mempool/) does not mean a miner will include it. This study follows those transactions from the mempool into blocks: which ones are mined, which pools mine them, and how long each waits first.

## The data it will use

"bitcoind mempool against the blocks that follow": the Labs node, comparing what its mempool held with what the next blocks contained. It is a descriptive card; no results are claimed.

## Related research

It extends the Live project [sub-1 sat/vB relay](/research/sub-1-sat-vb-relay/). [The sub-1 sat/vB share](/research/sub-1-sat-vb-share/) measures how much of the mempool pays below 1 sat/vB. The [policy observatory](/research/policy-observatory/) counts sub-1 sat/vB transactions among those that standard relay would refuse, and [fee rate](/concepts/fee-rate/) explains the unit.

Sources:

- The blockspacelabs.com page (index.html) · https://blockspacelabs.com
- Blockspace Holdings records

Live figures: relay as of block 972,320, 2026-10-20 12:17:53 UTC

Updated: 2026-10-20