The collapse in global travel has forced airlines to finally pull back the curtains on their crown jewels. having mortgaged planes and flight routes to secure new financing, us carriers have had to turn to their own loyalty programmes. the revelations suggest the entire sector deserves a re-evaluation once the pandemic is over.

Presentations submitted to investors have revealed in minute details just how lucrative the programmes can be. deltas skymiles programme, for example, generated $6.1bn in cash sales in 2019. that works out to 13 per cent of total group revenue. in terms of profits, the scheme carries even more weight. the $2.5bn in net profit it recorded accounted for more than half of deltas total net income last year.

United has reported that its programme is similarly profitable. the companys mileageplus scheme made $1.57bn in net profit more than half of group total for 2019.

In some cases, third-party valuations for loyalty schemes have surpassed the market value of the airlines themselves. american airlines claims that its aadvantage programme is worth between $19.5bn and $31.5bn far more than the companys own market capitalisation, which is now less than $7bn. on point loyalty, a consultancy, values skymiles at almost $26bn and mileageplus at about $20bn. that compares to deltas market value of $21.6bn and uniteds $11bn.

Big airlines have long treated the economics of their frequent-flyer programmes as a closely guarded secret. now that delta, american and united have been compelled to open up, their valuations should rise too.