France's Roman Catholic Church has reported a 1.3m-euro deficit ($1.6m) from a visit by the Pope to the southern shrine of Lourdes.
Hundreds of thousands came to see the frail pontiff at Lourdes
The two-day event culminated in a Mass attended by 200,000 people on Sunday.
However, donations covered only 15% of the expenditures for the weekend-long pilgrimage, a French bishop said.
He blamed the shortfall on a poor collection system, and urged Roman Catholics to help the Church recover the costs through extra donations.
The Church did not exceed its estimated budget of 1.5m euros ($1.85m), Lourdes Bishop Jacques Perrier said.
However, receipts from collections amounted to a mere 200,000 euros ($250,000).
"Organisers did not explain to pilgrims how things worked," he told the French AFP news agency.
"People are used to giving in churches, but not at big rallies," he added.
The bishop called on the faithful to help make up the deficit.
"We are appealing to the generosity of the Catholics," he said.
The main event was the Mass celebrated by Pope John Paul II on Sunday to mark the Feast of the Assumption.
The Feast celebrates the ascent into heaven of Mary, mother of Jesus Christ.
Lourdes is a popular shrine for Roman Catholics.
Six million pilgrims, many of them very ill, come to seek healing and to worship there each year.
It was in Lourdes that a young girl, Bernadette Soubirous, claimed to have witnessed visions of the Virgin Mary in a cave in the 19th Century.