Foundation Single Crochet
a stretchy, chain-free starting row that builds the base and first row in one pass

Foundation single crochet combines the starting chain and the first row of single crochet into one step. Instead of chaining a foundation row and then working single crochet into each chain, each foundation stitch builds its own "chain" as you go, so you get the base and the first row at the same time. The result is stretchier and less prone to the tight, twisted starting chain many crocheters fight with.
Because UK "single crochet" is the stitch US crocheters call "slip stitch," the UK name for this technique lines up with the UK term for what US crocheters call double crochet: UK crocheters call the equivalent technique "foundation double crochet (fdc)." Same technique, different name, following the standard one-step naming shift between the two systems.
How to work it
- Chain 2. This forms the base of your first foundation stitch.
- Insert your hook into the second chain from the hook, yarn over, and pull up a loop. You now have 2 loops on your hook.
- Yarn over and pull through 1 loop only. This creates the "chain" part of the next foundation stitch.
- Yarn over and pull through both remaining loops. This completes the "stitch" part, same as a regular single crochet.
- For the next foundation stitch, insert your hook under the two loops of the chain part made in step 3, and repeat steps 2 through 4.
- Continue until you have the number of foundation stitches the pattern calls for.
When to use it
Use foundation single crochet when a project needs a starting edge with more stretch than a standard chain gives, such as garment hems, blanket edges, or amigurumi worked flat before seaming. It takes more practice to keep an even tension than a standard chain-plus-row-one approach, so many crocheters learn it after they're comfortable with single crochet.