A urea production process comprising: A) subjecting ammonia and carbon dioxide to urea-forming conditions in a high pressure reaction zone thereby forming a first urea solution which also comprises carbamate, B) subjecting the first urea solution to high pressure stripping to decompose carbamate using heat (H1, S1), thereby forming a gas stream and a second urea solution also containing carbamate, and subjecting said gas stream to condensation in a high pressure carbamate condenser (HPCC), thereby forming a first carbamate-containing solution and releasing heat of condensation (H2, S2), wherein the carbamate-containing solution is supplied to the high pressure reaction zone, C) subjecting said second urea solution to low pressure carbamate decomposition, or first processing said second urea solution at medium pressure and subjecting the processed second urea solution (U2a) to low pressure decomposition, wherein said low pressure carbamate decomposition involves heating in a low pressure decomposer the urea solution (U2, U2a) containing carbamate using said heat of condensation (H2, S2) from the high pressure carbamate condenser to decompose carbamate, thereby giving a first vapor and a third urea solution also containing carbamate, and expanding the third urea solution to a sub-atmospheric pressure (F1, X1) thereby obtaining an expanded third urea solution (U3a), D) subjecting said first vapor to condensation in a first low pressure carbamate condenser, thereby obtaining a second carbamate-containing solution and second vapor and releasing additional heat of condensation, wherein the first low pressure carbamate condenser has an outlet for the second carbamate-containing solution in liquid communication with an inlet of the high pressure reaction zone, and subjecting said expanded third urea solution (U3a) to decomposition of carbamate in a sub-atmospheric decomposer (LLPD) using said additional heat of condensation from said first low pressure carbamate condenser by heat transfer through a heat-exchanging wall (LPHX) between said first low pressure carbamate condenser and said sub-atmospheric decomposer (LLPD), thereby obtaining a fourth urea solution and a third vapor, and E) subjecting said third vapor to condensation in a sub-atmospheric carbamate condenser (LLPC), in indirect heat exchange with cooling fluid, thereby obtaining a fourth carbamate-containing solution. A) subjecting ammonia and carbon dioxide to urea-forming conditions in a high pressure reaction zone thereby forming a first urea solution which also comprises carbamate, B) subjecting the first urea solution to high pressure stripping to decompose carbamate using heat (H1, S1), thereby forming a gas stream and a second urea solution also containing carbamate, and subjecting said gas stream to condensation in a high pressure carbamate condenser (HPCC), thereby forming a first carbamate-containing solution and releasing heat of condensation (H2, S2), wherein the carbamate-containing solution is supplied to the high pressure reaction zone, C) subjecting said second urea solution to low pressure carbamate decomposition, or first processing said second urea solution at medium pressure and subjecting the processed second urea solution (U2a) to low pressure decomposition, wherein said low pressure carbamate decomposition involves heating in a low pressure decomposer the urea solution (U2, U2a) containing carbamate using said heat of condensation (H2, S2) from the high pressure carbamate condenser to decompose carbamate, thereby giving a first vapor and a third urea solution also containing carbamate, and expanding the third urea solution to a sub-atmospheric pressure (F1, X1) thereby obtaining an expanded third urea solution (U3a), D) subjecting said first vapor to condensation in a first low pressure carbamate condenser, thereby obtaining a second carbamate-containing solution and second vapor and releasing additional heat of condensation, wherein the first low pressure carbamate condenser has an outlet for the second carbamate-containing solution in liquid communication with an inlet of the high pressure reaction zone, and subjecting said expanded third urea solution (U3a) to decomposition of carbamate in a sub-atmospheric decomposer (LLPD) using said additional heat of condensation from said first low pressure carbamate condenser by heat transfer through a heat-exchanging wall (LPHX) between said first low pressure carbamate condenser and said sub-atmospheric decomposer (LLPD), thereby obtaining a fourth urea solution and a third vapor, and E) subjecting said third vapor to condensation in a sub-atmospheric carbamate condenser (LLPC), in indirect heat exchange with cooling fluid, thereby obtaining a fourth carbamate-containing solution.