From September 1, holders of a BP Plus UK or Totalcard will be able to use them at the other oil company's filling stations.
The link applies only to those two cards and both companies emphasise they remain rivals – any suggestion of a new combined card is ruled out. The oil giants believe though that both will benefit from opening up their individual UK networks to each other.
Informal talks began three years ago and the final arrangements are now in place. Both are confident that testing has removed potential technological problems.
The combined network has more than 2,100 sites (BP's 1,325 plus Total's just under 900). BP has more than 200,000 fuel card holders and Total 120,000.
BP's network includes 59 motorway sites – Total has only two but is strong in urban areas. Conversely, BP is relatively weak in the south-west, Wales and along the east coast, while Total has a similar problem in Scotland.
Gordon Balmer, UK country manager at BP European Fleet Services, said: 'This agreement underlines our commitment to the car and van sector, and improves our service to BP Plus UK card holders.'
Douglas Paton, card services manager at Total, added: 'We have already improved security for Totalcard holders and they will soon have access to the largest forecourt network in the UK.'
Neither company is revealing the scale of investment in the partnership but each is confident of justifying it through increased forecourt traffic.
Balmer said: 'Where each of us has sites is as important as the scale of the network, and also the facilities we offer to our card holders. Together we offer quality.'
BP/Total together have little more than a tenth of the total number of fuel outlets where Arval PHH's AllStar card can be used under a franchising arrangement. Allstar also has a tie-up with some supermarkets where low prices are attractive to fleet managers.
Paton said: 'Pricing is not as big an issue as it used to be, because supermarkets are often not that much cheaper. We can offer our fuel card users services associated with use of the card that are more important than the saving.'
Total's was the first national fuel card with over-the-counter PIN verification, though the system is now being introduced at BP stations and more widely in the latest anti-fraud initiative.
By next year, EU legislation will insist that all businesses accepting credit or debit cards in the UK must have the facility to check in-card microchips and demand pin numbers.
BP offers eBilling (free online access to invoices to reduce paperwork) and eReporting, a fleet data management system which includes fuel consumption calculations and automatically highlights discrepancies.
Through On-Line Account Manager, BP provides viewing of transactions and account details plus reporting/replacing lost or stolen cards. Pre-figuring of the cards excludes unauthorised purchases, and the system includes a fast-stop procedure to limit losses if a card goes missing.
BP and Total have vowed not to reduce the scale of their networks in the light of the agreement, and will continue with their individual pricing policies.
The arrangement relates solely to the UK because fleet drivers making regular business trips to the continent use other cards issued by the two companies. Neither company sees this as a disadvantage, because UK fleet fuel card demand is largely for use in this country. The restriction also prevents the potential abuse of the cards when holders are abroad on holiday.
The agreement does not cover BP's Plus Europa and Bunker Plus cards, or Total Eurotraffic cards. Nor does it extend to loyalty cards – Nectar cards will not be accepted at Total stations and the same applies to Total's Tops cards at BP outlets. Customers will be at liberty to use their cards to purchase any products indicated at the other's company fuel stops.
Legally, this is not a multi-partner agreement, and this means the partial partnership will not affect any cross-acceptance agreements signed by Total or BP with other companies.
Virtually all UK sites are included. The exceptions are those in the Channel Islands and, until technical problems are resolved by the end of the year, a few UK mainland forecourts.
BP and Total want to foster loyalty at a time when fuel card holders are demanding an improved service. Datamonitor last year suggested that one in four are discontented with the service they receive.
The two oil companies believe their best chance of retaining or increasing the market share is by emphasising the services extended to users.