Limestone calcined clay cements (LC3) are a promising low-carbon alternative to ordinary Portland cement (OPC). Early-age shrinkage and viscoelastic behavior are investigated in a multi-technique experimental study of three binders, including OPC, limestone Portland cement (LPC, containing 70%mass OPC and 30%mass limestone), and LC3 (containing 70%mass OPC, 15%mass limestone, and 15%mass calcined clay). The cement pastes are all prepared at the same initial water-to-solid mass ratio (w/s = 0.45). Reaction kinetics are obtained from quasi-isothermal calorimetry tests. Macroscopic mechanical tests include uniaxial compressive strength testing, ultrasound pulse velocimetry measurements, and three-minute creep tests performed hourly from 1 to 7 days after paste production. An advanced test evaluation protocol allows precise identification of the elastic modulus, the creep modulus, and the creep exponent without relying on constraining assumptions. The test evaluation shows that the creep deformation developed during the few seconds of the load application phase amounts to some 20% to 60% of the total creep deformation at the end of the three-minute load plateau. This highlights the need to account for instantaneous and time-dependent deformations already during the load application phase. The test evaluation protocol allows for considering shrinkage. However, shrinkage strains account for only some 3% of the total measured strains, so disregarding shrinkage strains also leads to meaningful results. The LC3 paste was found to be less creep active than the LPC paste, slightly more creep active than the OPC paste from 1 to 3 days after paste production, and less creep active than the OPC paste from a material age of about 3 days. Macroscopic creep and shrinkage of the OPC, LPC, and LC3 pastes are qualitatively related to the microstructural phase evolution of the binders, as analyzed by CemGEMS. The multiscale interpretation suggests that the S-shaped shrinkage evolution, the rapid stiffness increase, and the low creep activity of the LC3 paste result from Portlandite dissolution, pore refinement by C-A-S-H phases, and precipitation of AFm phases.