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We demonstrate halving the record-low loss of interconnection between a nested antiresonant nodeless type hollow-core fiber (NANF) and standard single-mode fiber (SMF). The achieved interconnection loss of 0.15 dB is only 0.07 dB above the theoretically-expected minimum loss. We also optimized the interconnection in terms of unwanted cross-coupling into the higher-order modes of the NANF. We achieved cross-coupling as low as− 35 dB into the LP mode (the lowest-loss higher-order mode and thus the most important to eliminate). With the help of simulations, we show that the measured LP mode coupling is most likely limited by the slightly imperfect symmetry of the manufactured NANF. The coupling cross-talk into the highly-lossy LP mode ( dB/km in our fiber) was measured to be below− 22 dB. Furthermore, we show experimentally that the anti-reflective coating applied to the interconnect interface …