Across in Moto3, Maverick Vinales had kept up his own impressive testing form over the opening three days, but a crash forced him to spend the final day in hospital. Luis Salom jumped him late on to end fastest, with Vinales second.
Both Espargaro, who finished runner-up to Marc Marquez in last year's Moto2 championship, and Vinales - third in Moto3 last year - had also headed the previous Valencia and Jerez tests in February.
Espargaro's time, a 1m42.636s set on the penultimate day, left him nearly half a second clear of the field.
Kalex riders filled the top six courtesy of Takaaki Nakagami, Julian Simon, Toni Elias, Scott Redding and Espargaro's Tuenti team-mate Esteve Rabat.
Nicolas Terol on the Aspar Suter was the only non-Kalex rider to get within one second of Espargaro's benchmark.
In Moto3 Vinales had also kept himself top of the timesheets at the end of the penultimate day, his 1m46.603s enough to edge out Alex Rins by just under one tenth of a second.
His day – and test – was brought to a premature end however when he trapped his hand under his bike during a fall. He lost a nail and damaged the tissue of his fingertip, prompting a visit to MotoGP doctor Xavier Mir.
He sat out the final day in order to undergo reconstructive surgery.
He was therefore unable to respond when, in the final moments of the last session, Luis Salom worked his way down to a 1m46.374s to end the final test on top.
Vinales stayed second, seven thousandths of a second ahead of Rins. Alex Marquez and Jonas Folger made it a top-five sweep for KTM, with Miguel Oliveira putting his Mahindra sixth, 1.1s down.
The first race of both the Moto2 and Moto3 seasons takes place at Qatar on April 7.
Moto2 combined times:
1. Pol Espargaro Pons Kalex 1m42.636s
2. Takaaki Nakagami Italtrans Kalex 1m43.103s + 0.467s
3. Julian Simon Italtrans Kalex 1m43.188s + 0.552s
4. Toni Elias Avintia Kalex 1m43.365s + 0.729s
5. Scott Redding Marc VDS Kalex 1m43.372s + 0.736s
6. Esteve Rabat Pons Kalex 1m43.424s + 0.788s
7. Nicolas Terol Aspar Suter 1m43.438s + 0.802s
8. Jordi Torres Aspar Suter 1m43.641s + 1.005s
9. Xavier Simeon SAG Kalex 1m43.720s + 1.084s
10. Mika Kallio Marc VDS Kalex 1m43.774s + 1.138s
11. Dominique Aegerter Technomag Suter 1m43.800s + 1.164s
12. Axel Pons Pons Kalex 1m43.861s + 1.225s
13. Alex de Angelis Forward Speed Up 1m43.925s + 1.289s
14. Simone Corsi Forward Speed Up 1m43.934s + 1.298s
15. Johann Zarco Ioda Suter 1m43.993s + 1.357s
16. Anthony West QMMF Speed Up 1m44.052s + 1.416s
17. Randy Krummenacher Technomag Suter 1m44.089s + 1.453s
18. Mike di Meglio JIR Motobi 1m44.158s + 1.522s
19. Sandro Cortese Intact Kalex 1m44.276s + 1.640s
20. Danny Kent Tech 3 1m44.350s + 1.714s
21. Ratthapark Wilairot Gresini Suter 1m44.456s + 1.820s
22. Mattia Pasini Forward Speed Up 1m44.538s + 1.902s
23. Ricky Cardus Forward Speed Up 1m44.572s + 1.936s
24. Yuki Takahashi Tady Moriwaki 1m44.839s + 2.203s
25. Steven Odendaal Arginano Speed Up 1m44.848s + 2.212s
26. Marcel Schrotter SAG Kalex 1m44.905s + 2.269s
27. Louis Rossi Tech 3 1m45.181s + 2.545s
28. Kyle Smith Avintia Kalex 1m45.314s + 2.678s
29. Sergio Gadea Gresini Suter 1m46.041s + 3.405s
30. Rafid Topan Sucipto QMMF Speed Up 1m46.283s + 3.647s
31. Alberto Moncayo Arginano Speed Up 1m46.410s + 3.774s
32. Doni Tata Pradita Gresini Suter 1m46.649s + 4.013s
Moto3 combined times:
1. Luis Salom Ajo KTM 1m46.374s
2. Maverick Vinales Laglisse KTM 1m46.603s + 0.229s
3. Alex Rins Monlau KTM 1m46.610s + 0.236s
4. Alex Marquez Monlau KTM 1m46.986s + 0.612s
5. Jonas Folger Aspar Kalex-KTM 1m47.010s + 0.636s
6. Miguel Oliveira Mahindra 1m47.548s + 1.174s
7. Brad Binder Ambrogio Suter-Honda 1m47.701s + 1.327s
8. Eric Granado Aspar Kalex-KTM 1m47.742s + 1.368s
9. Niklas Ajo Avant KTM 1m47.787s + 1.413s
10. Jakub Kornfeil RW Kalex-KTM 1m47.854s + 1.480s
11. Arthur Sissis Ajo KTM 1m47.861s + 1.487s
12. Danny Webb Ambrogio Suter-Honda 1m47.959s + 1.585s
13. Niccolo Antonelli Gresini FTR-Honda 1m48.031s + 1.657s
14. Jack Miller RTG FTR-Honda 1m48.038s + 1.664s
15. Isaac Vinales Ongetta FTR-Honda 1m48.088s + 1.714s
16. Efren Vazquez Mahindra 1m48.095s + 1.721s
17. Zulfahmi Khairuddin Ajo KTM 1m48.191s + 1.817s
18. Romano Fenati Italia FTR-Honda 1m48.214s + 1.840s
19. Alexis Masbou Ongetta FTR-Honda 1m48.253s + 1.879s
20. John McPhee RTG FTR-Honda 1m48.552s + 2.178s
21. Livio Loi Marc VDS Kalex-KTM 1m48.568s + 2.194s
22. Lorenzo Baldassarri Gresini FTR-Honda 1m48.819s + 2.445s
23. Alessandro Tonucci Tasca Honda 1m48.859s + 2.485s
24. Jasper Iwema RW Kalex-KTM 1m48.868s + 2.494s
25. Francesco Bagnaia Italia FTR-Honda 1m48.886s + 2.512s
26. Toni Finsterbusch Kiefer Kalex-KTM 1m48.988s + 2.614s
27. Alan Techer CIP TSR-Honda 1m49.129s + 2.755s
28. Juanfran Guevara CIP TSR-Honda 1m49.186s + 2.812s
29. Philipp Oettl Paddock Kalex-KTM 1m49.248s + 2.874s
30. Matteo Ferrari Ongetta FTR-Honda 1m49.299s + 2.925s
31. Ana Carrasco Laglisse KTM 1m49.479s + 3.105s
32. Florian Alt Kiefer Kalex-KTM 1m49.740s + 3.366s
33. Hyuga Watanabe Tasca Honda 1m50.332s + 3.958s