A low price can be irregular if your cost calculation is poor
If your bid is unrealistically low and your cost calculation is incomplete, the contracting authority may reject you because you haven't included all required costs.
What happened?
A company bid on a cleaning contract for motorways. The cost calculation showed two employees but no van — while the specifications clearly stated that each team needed at least two workers plus a vehicle. Lux Green said the van cost was 'implicit' in the hourly rate, but the calculator couldn't demonstrate this. The court said: your calculation is incomplete — that makes your price abnormal.
Why does this matter?
This ruling shows that low prices don't always win — if your cost calculation has gaps, you get rejected. The contracting authority may force you to justify your prices. This protects against loss-making contractors.
The lesson
In your cost calculation, every required cost category (equipment, personnel, overhead) must be separately visible. Never say 'implicit' — everything must be explicit. Check your bid against all requirements in the specifications: have you really included everything?
Check yourself
Can I defend every line of my cost calculation against someone who asks why I haven't included a van?