Railings is F&B's near-black with a soft blue-grey undertone — that bit of warmth and depth is why people love it on front doors, railings (the clue's in the name) and dramatic interiors. The good news is you don't have to pay the F&B premium to get it.
Dulux Basically Black (LRV 7.3) comes in at ΔE 1.9 from the original. Crown Anthracite (also LRV 7.3) matches it identically at ΔE 1.9. Both are under 2.5, which means very close — close enough that nobody's standing in your hallway clocking the difference. Crown and Dulux trade tins are widely stocked and a fair bit cheaper per litre, so this is an easy win.
If you want something a touch deeper and more characterful, COAT The Record Store (LRV 5.2) sits at ΔE 3.7 — not a dead match, but in the same near-black family with a slightly darker, moodier read. COAT's a cracking brand for low-VOC, fast-drying water-based finishes if that matters to you.
The "but what about" here: don't expect a budget tin to behave exactly like F&B at the brush. F&B's Estate Eggshell and Exterior Eggshell have a specific flat-ish sheen and flow that's part of what you're paying for. The colour will match; the finish and coverage might differ. For a front door or metal railings, prime properly first — Zinsser Cover Stain on bare or dodgy substrates, and use an exterior-grade eggshell topcoat whichever brand you pick.
My honest steer: for interior walls or woodwork, go Dulux Basically Black or Crown Anthracite and pocket the savings. If it's an exterior door taking weather, the F&B Exterior Eggshell is worth its money for durability — but match the cheaper colour for everything inside.
Always order a sample pot and test it on the actual surface in your own light before you commit. Near-blacks shift a lot between daylight and lamplight.