Spain's treasury raised €4.513 billion ($5.8 billion) in a sale of two-, five- and 10-year bonds, exceeding its own target range of 3.0–4.0 billion as demand outstripped supply by nearly three to one.
The rate of return demanded by investors eased slightly from similar bond issues in the past month.
Spanish borrowing costs have dropped significantly since the European Central Bank (ECB) last September vowed to intervene on the markets if Spain sought its help.
Ruling Popular Party prime minister Mariano Rajoy, a conservative, resisted pressure last year to seek a sovereign bailout or ask the ECB for help, though he praised the central bank for offering important support.
A key measure of investors' perceptions of the risk of investing in Spain, the extra rate of return demanded on Spanish government 10-year bonds compared with that of benchmark German Bunds, eased to 351 percentage points in morning trade from 359 points at Wednesday's close.
A Bank of Spain report on the latest bond sale showed that Spain sold €2.325 billion in benchmark 10-year bonds, offering a yield of 4.898 percent, down from 4.917 percent in the previous comparable auction March 7th.
Spain also raked in €1.032 billion in the sale of five-year bonds, which offered a yield of 3.557 percent, down from 3.572 percent on March 7th.
The treasury brought in another €1.156 billion in the sale of two-year bonds, offering a yield of 2.275 percent, down from 2.54 percent on February 21st.